What makes a code an add-on code
CMS defines an add-on code as one that, with rare exceptions, is performed together with a primary service by the same practitioner and is rarely payable when it is the only procedure reported. Add-on codes let a claim show significant extra work, such as an additional graft area, an extra vessel or another half hour, without a separate code for every combination. They are not a way to bill a portion of a service: work that is merely necessary to complete the primary procedure, or a complication handled during it, is included in the primary code. The add-on code edit file is CMS's list of add-on codes and the primary codes each one may be reported with, built from CPT instructions, HCPCS descriptors and CMS coding policy; Chapter I of the NCCI Policy Manual sets out the rules.
Most procedure-to-procedure pairs do not involve add-on codes, because an edit that denies the primary procedure already takes the add-on down with it. The PTP tables add pairs for a few add-on codes where that is not enough, which is why the operating microscope and intraoperative monitoring add-ons appear as column-two codes in many pairs.
The three add-on edit types
Each add-on code carries one edit type. Type 1 is by far the most common; the 42 type 2 codes have one placeholder row each (primary code CCCCC) that tells contractors to define the primaries.
| Type | Rule | Add-on codes | Edits | HCPCS Level II | CPT |
|---|---|---|---|---|---|
| Type 1 | CMS lists every acceptable primary code. The add-on is paid only with one of them. | 669 | 7,130 | 28 | 641 |
| Type 2 | CMS lists no primary codes. Each Medicare contractor decides which primaries it accepts. | 42 | 42 | 11 | 31 |
| Type 3 | CMS lists some primary codes. Contractors accept those and may accept others they define. | 12 | 571 | 3 | 9 |
When the primary is missing: the denial and the fix
On practitioner claims the contractor denies the add-on line when no accepted primary is billed for the same patient, usually with CARC 107 and remark N122. Institutional claims go through the Integrated Outpatient Code Editor, which has one add-on edit per type: edit 106 for type 1, 107 for type 2 and 108 for type 3, each a line item denial that can be appealed but not simply resubmitted. It applies them on the bill types its specification lists, such as critical access hospital claims (bill type 085x), and returns edit 107 only on a critical access hospital's professional service lines (revenue codes 096x to 098x). On a standard OPPS hospital outpatient claim (bill type 013x) only edit 106 applies, and only to remote mental health and software-as-a-service add-on codes; the I/OCE edit list shows each edit's disposition and the claim types it is listed for. The usual causes are a primary billed on another claim or under another provider number, a primary that was itself denied by a pair edit, an add-on keyed with the wrong primary after a code update, and a type 2 or type 3 add-on paired with a primary the contractor does not accept. Fix the claim by adding or correcting the primary where the record supports it, or remove the add-on.
Two pairs from the same file show the check. G2211 is a type 1 add-on with 18 listed primaries: with 99213 it meets the requirement (run G2211 with 99213), and with 36415 alone it is an add-on code without a listed primary (run G2211 with 36415). The NCCI edit checker runs this add-on check on any pair, next to the bundling answer.
HCPCS Level II add-on codes
All 42 Level II add-on codes in the edit file, with the CMS descriptor from the October HCPCS file. Primary codes are shown as numbers; a code with a reference page links to it.
| Code | Descriptor | Type | Listed primaries |
|---|---|---|---|
| C7902 | Service for diagnosis, evaluation, or treatment of a mental health or substance use disorder, each additional 15 minutes, provided remotely by hospital staff who are licensed to provide mental health services… | Type 1 | 2: C7900, C7901 |
| C8937 | Computer-aided detection, including computer algorithm analysis of breast mri image data for lesion detection/characterization, pharmacokinetic analysis, with further physician review for interpretation… | Type 1 | 6: 77046, 77047, C8903, C8905, C8906, C8908 |
| C9601 | Percutaneous transcatheter placement of drug-eluting intracoronary stent(s), with coronary angioplasty when performed; each additional branch of a major coronary artery… | Type 1 | 10: 92928, 92933, 92937, 92941, 92943, C9600, … |
| C9603 | Percutaneous transluminal coronary atherectomy, with drug-eluting intracoronary stent, with coronary angioplasty when performed; each additional branch of a major coronary artery… | Type 1 | 8: 92933, 92937, 92941, 92943, C9602, C9604, … |
| C9605 | Percutaneous transluminal revascularization of or through coronary artery bypass graft (internal mammary, free arterial, venous), any combination of drug-eluting intracoronary stent, atherectomy and angioplasty… | Type 1 | 2: 92937, C9604 |
| C9608 | Percutaneous transluminal revascularization of chronic total occlusion, coronary artery, coronary artery branch, or coronary artery bypass graft, any combination of drug-eluting intracoronary stent, atherectomy… | Type 1 | 11: 92924, 92928, 92933, 92937, 92941, 92943, … |
| C9726 | Placement and removal (if performed) of applicator into breast for intraoperative radiation therapy, add-on to primary breast procedure | Type 3: MAC may add primaries | 2: 19301, 19302 |
| C9738 | Adjunctive blue light cystoscopy with fluorescent imaging agent (list separately in addition to code for primary procedure) | Type 3: MAC may add primaries | 3: 52204, 52214, 52224 |
| C9756 | Intraoperative near-infrared fluorescence lymphatic mapping of lymph node(s) (sentinel or tumor draining) with administration of indocyanine green (icg) (list separately in addition to code for primary procedure) | Type 2: MAC defines primaries | None listed |
| C9768 | Endoscopic ultrasound-guided direct measurement of hepatic portosystemic pressure gradient by any method (list separately in addition to code for primary procedure) | Type 2: MAC defines primaries | None listed |
| C9776 | Intraoperative near-infrared fluorescence imaging of major extra-hepatic bile duct(s) (e.g., cystic duct, common bile duct and common hepatic duct) with intravenous administration of indocyanine green (icg)… | Type 2: MAC defines primaries | None listed |
| G0018 | Psychotherapy for crisis furnished in an applicable site of service (any place of service at which the non-facility rate for psychotherapy for crisis services applies, other than the office setting); each additional 30… | Type 1 | 1: G0017 |
| G0022 | Community health integration services, each additional 30 minutes per calendar month (list separately in addition to g0019) | Type 1 | 1: G0019 |
| G0024 | Principal illness navigation services, additional 30 minutes per calendar month (list separately in addition to g0023) | Type 1 | 1: G0023 |
| G0137 | Intensive outpatient services; weekly bundle, minimum of 9 services over a 7 contiguous day period, which can include individual and group therapy with physicians or psychologists… | Type 2: MAC defines primaries | None listed |
| G0146 | Principal illness navigation - peer support, additional 30 minutes per calendar month (list separately in addition to g0140) | Type 1 | 1: G0140 |
| G0247 | Routine foot care by a physician of a diabetic patient with diabetic sensory neuropathy resulting in a loss of protective sensation (lops) to include, the local care of superficial wounds… | Type 1 | 2: G0245, G0246 |
| G0278 | Iliac and/or femoral artery angiography, non-selective, bilateral or ipsilateral to catheter insertion, performed at the same time as cardiac catheterization and/or coronary angiography, includes positioning… | Type 1 | 10: 93452, 93453, 93454, 93455, 93456, 93457, … |
| G0279 | Diagnostic digital breast tomosynthesis, unilateral or bilateral (list separately in addition to 77065 or 77066) | Type 1 | 2: 77065, 77066 |
| G0289 | Arthroscopy, knee, surgical, for removal of loose body, foreign body, debridement/shaving of articular cartilage (chondroplasty) at the time of other surgical knee arthroscopy in a different compartment of the same knee | Type 1 | 17: 29871, 29873, 29874, 29875, 29876, 29877, … |
| G0316 | Prolonged hospital inpatient or observation care evaluation and management service(s) beyond the total time for the primary service… | Type 1 | 3: 99223, 99233, 99236 |
| G0317 | Prolonged nursing facility evaluation and management service(s) beyond the total time for the primary service (when the primary service has been selected using time on the date of the primary service); each additional… | Type 1 | 2: 99306, 99310 |
| G0318 | Prolonged home or residence evaluation and management service(s) beyond the total time for the primary service (when the primary service has been selected using time on the date of the primary service); each additional… | Type 1 | 2: 99345, 99350 |
| G0453 | Continuous intraoperative neurophysiology monitoring, from outside the operating room (remote or nearby), per patient, (attention directed exclusively to one patient) each 15 minutes… | Type 1 | 28: 95822, 95860, 95861, 95863, 95864, 95865, … |
| G0501 | Resource-intensive services for patients for whom the use of specialized mobility-assistive technology (such as adjustable height chairs or tables, patient lift, and adjustable padded leg supports) is medically… | Type 2: MAC defines primaries | None listed |
| G0506 | Comprehensive assessment of and care planning for patients requiring chronic care management services (list separately in addition to primary monthly care management service) | Type 3: MAC may add primaries | 46: 99202, 99203, 99204, 99205, 99212, 99213, … |
| G0513 | Prolonged preventive service(s) (beyond the typical service time of the primary procedure), in the office or other outpatient setting requiring direct patient contact beyond the usual service; first 30 minutes… | Type 1 | 17: 76706, 76977, 77063, 77067, 77078, 77080, … |
| G0514 | Prolonged preventive service(s) (beyond the typical service time of the primary procedure), in the office or other outpatient setting requiring direct patient contact beyond the usual service; each additional 30 minutes… | Type 1 | 1: G0513 |
| G0532 | Take-home supply of nasal nalmefene hydrochloride; one carton of two, 2.7 mg per 0.1 ml nasal sprays (provision of the services by a medicare-enrolled opioid treatment program)… | Type 2: MAC defines primaries | None listed |
| G0534 | Coordinated care and/or referral services, such as to adequate and accessible community resources to address unmet health-related social needs, including harm reduction interventions and recovery support services… | Type 2: MAC defines primaries | None listed |
| G0535 | Patient navigational services, provided directly or by referral; including helping the patient to navigate health systems and identify care providers and supportive services, to build patient self-advocacy… | Type 2: MAC defines primaries | None listed |
| G0536 | Peer recovery support services, provided directly or by referral; including leveraging knowledge of the condition or lived experience to provide support, mentorship, or inspiration to meet oud treatment and recovery… | Type 2: MAC defines primaries | None listed |
| G0540 | Caregiver training in behavior management/modification for parent(s)/guardian(s)/caregiver(s) of patients with a mental or physical health diagnosis, administered by physician or other qualified health care professional… | Type 1 | 1: G0539 |
| G0542 | Caregiver training in direct care strategies and techniques to support care for patients with an ongoing condition or illness and to reduce complications… | Type 1 | 1: G0541 |
| G0545 | Visit complexity inherent to hospital inpatient or observation care associated with a confirmed or suspected infectious disease by an infectious diseases specialist, including disease transmission risk assessment… | Type 1 | 15: 99221, 99222, 99223, 99231, 99232, 99233, … |
| G0554 | Each additional 20 minutes of monthly treatment management services directly related to the patient's therapeutic use of the digital mental health treatment (dmht) device that augments a behavioral therapy plan… | Type 1 | 1: G0553 |
| G0561 | Tympanostomy with local or topical anesthesia and insertion of a ventilating tube when performed with tympanostomy tube delivery device, unilateral (list separately in addition to 69433)… | Type 1 | 1: 69433 |
| G2076 | Intake activities, including initial medical examination that is conducted by an appropriately licensed practitioner and preparation of a care plan, which may be informed by administration of a standardized… | Type 2: MAC defines primaries | None listed |
| G2077 | Periodic assessment; assessing periodically by an otp practitioner and includes a review of moud dosing, treatment response, other substance use disorder treatment needs, responses and patient-identified goals… | Type 2: MAC defines primaries | None listed |
| G2088 | Office-based treatment for opioid use disorder, including care coordination, individual therapy and group therapy and counseling; each additional 30 minutes beyond the first 120 minutes… | Type 1 | 2: G2086, G2087 |
| G2211 | Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part… | Type 1 | 18: 99202, 99203, 99204, 99205, 99211, 99212, … |
| G2212 | Prolonged office or other outpatient evaluation and management service(s) beyond the maximum required time of the primary procedure which has been selected using total time on the date of the primary service; each… | Type 1 | 4: 99205, 99215, 99483, G0463 |
CPT add-on codes by code range
The 681 CPT add-on codes are listed by number only, because CPT descriptors are licensed by the American Medical Association. The number after each code is how many primary codes the edit file lists for it; a code marked with an asterisk also lets the contractor define primaries. Grouped by the policy manual chapter that covers the range, the list shows where add-on codes concentrate: Chapter XI (CPT 90000-99999) with 148, Chapter V (CPT 30000-39999) with 115 and Chapter XIII (CPT Category III 0001T-0999T) with 112.
Chapter II (CPT 00000-01999): 3 add-on codes
01953 (1) · 01968 (1) · 01969 (1)
Chapter III (CPT 10000-19999): 69 add-on codes
10004 (1) · 10006 (1) · 10008 (1) · 10010 (1) · 10012 (1) · 10036 (1) · 11001 (1) · 11008 (4) · 11045 (1) · 11046 (1) · 11047 (1) · 11103 (3) · 11105 (2) · 11107 (1) · 11201 (1) · 11732 (1) · 11922 (1) · 13102 (1) · 13122 (1) · 13133 (1) · 13153 (1) · 14302 (1) · 15003 (1) · 15005 (1) · 15012 (1) · 15014 (1) · 15016 (1) · 15018 (1) · 15101 (1) · 15111 (1) · 15116 (1) · 15121 (1) · 15131 (1) · 15136 (1) · 15151 (1) · 15152 (1) · 15156 (1) · 15157 (1) · 15201 (1) · 15221 (1) · 15241 (1) · 15261 (1) · 15272 (1) · 15274 (1) · 15276 (1) · 15278 (1) · 15772 (1) · 15774 (1) · 15777 (0*) · 15787 (1) · 15847 (1) · 15853 (23) · 15854 (23) · 16036 (1) · 17003 (1) · 17312 (1) · 17314 (1) · 17315 (4) · 19001 (1) · 19082 (1) · 19084 (1) · 19086 (1) · 19126 (1) · 19282 (1) · 19284 (1) · 19286 (1) · 19288 (1) · 19294 (2) · 19297 (2)
Chapter IV (CPT 20000-29999): 53 add-on codes
20700 (76) · 20701 (42) · 20702 (39) · 20703 (16) · 20704 (31) · 20705 (99) · 20930 (23) · 20931 (23) · 20932 (10) · 20933 (10) · 20934 (10) · 20936 (23) · 20937 (23) · 20938 (23) · 20939 (24) · 20985 (0*) · 22103 (3) · 22116 (3) · 22208 (2) · 22216 (3) · 22226 (3) · 22328 (3) · 22512 (2) · 22515 (2) · 22527 (1) · 22534 (2) · 22552 (1) · 22585 (3) · 22614 (5) · 22632 (3) · 22634 (1) · 22840 (112) · 22841 (112) · 22842 (112) · 22843 (112) · 22844 (112) · 22845 (112) · 22846 (112) · 22847 (112) · 22848 (112) · 22853 (112) · 22854 (112) · 22858 (1) · 22859 (112) · 22860 (1) · 22868 (1) · 22870 (1) · 26125 (1) · 26861 (1) · 26863 (1) · 27358 (3) · 27692 (2) · 29826 (11)
Chapter V (CPT 30000-39999): 115 add-on codes
31627 (16) · 31632 (1) · 31633 (1) · 31637 (1) · 31649 (1) · 31651 (1) · 31654 (11) · 32501 (3) · 32506 (1) · 32507 (10) · 32667 (1) · 32668 (14) · 32674 (78) · 33141 (51) · 33225 (22) · 33257 (161) · 33258 (45) · 33259 (118) · 33268 (0*) · 33277 (2) · 33367 (16) · 33368 (16) · 33369 (16) · 33370 (6) · 33419 (1) · 33508 (12) · 33509 (4) · 33517 (4) · 33518 (4) · 33519 (4) · 33521 (4) · 33522 (4) · 33523 (4) · 33530 (50) · 33572 (10) · 33746 (1) · 33768 (4) · 33866 (4) · 33904 (4) · 33924 (51) · 33929 (1) · 33987 (4) · 34709 (12) · 34711 (1) · 34713 (24) · 34714 (174) · 34715 (26) · 34716 (174) · 34717 (4) · 34808 (13) · 34812 (26) · 34813 (1) · 34820 (26) · 34833 (174) · 34834 (26) · 35306 (1) · 35390 (1) · 35400 (0*) · 35500 (24) · 35572 (82) · 35600 (4) · 35681 (0*) · 35682 (7) · 35683 (7) · 35685 (3) · 35686 (11) · 35697 (0*) · 35700 (10) · 36218 (4) · 36227 (3) · 36228 (4) · 36248 (2) · 36474 (1) · 36476 (1) · 36479 (1) · 36483 (1) · 36907 (16) · 36908 (16) · 36909 (6) · 37185 (1) · 37186 (0*) · 37237 (1) · 37239 (1) · 37247 (1) · 37249 (1) · 37252 (226) · 37253 (226) · 37255 (4) · 37257 (3) · 37259 (2) · 37261 (1) · 37262 (8) · 37264 (8) · 37266 (7) · 37268 (6) · 37270 (5) · 37272 (4) · 37274 (3) · 37276 (2) · 37278 (1) · 37279 (16) · 37281 (8) · 37283 (7) · 37285 (6) · 37287 (5) · 37289 (4) · 37291 (3) · 37293 (2) · 37295 (1) · 37297 (2) · 37299 (1) · 38102 (0*) · 38746 (51) · 38747 (0*) · 38900 (27)
Chapter VI (CPT 40000-49999): 24 add-on codes
43273 (11) · 43283 (3) · 43338 (11) · 43635 (4) · 44015 (0*) · 44121 (1) · 44128 (2) · 44139 (7) · 44203 (1) · 44213 (5) · 44701 (4) · 44955 (0*) · 47001 (0*) · 47542 (8) · 47543 (10) · 47544 (10) · 47550 (0*) · 48400 (0*) · 49326 (2) · 49327 (116*) · 49412 (0*) · 49435 (2) · 49623 (19) · 49905 (0*)
Chapter VII (CPT 50000-59999): 12 add-on codes
50606 (19) · 50705 (19) · 50706 (19) · 51797 (2) · 52442 (1) · 55715 (6) · 56606 (1) · 57267 (6) · 57465 (8) · 58110 (8) · 58611 (0*) · 59525 (6)
Chapter VIII (CPT 60000-69999): 75 add-on codes
60512 (12) · 60661 (1) · 61316 (20) · 61517 (2) · 61611 (4) · 61641 (1) · 61642 (1) · 61651 (1) · 61781 (0*) · 61782 (0*) · 61783 (0*) · 61797 (2) · 61799 (1) · 61800 (2) · 61864 (1) · 61868 (1) · 62148 (7) · 62160 (7) · 62331 (1) · 63032 (1) · 63035 (2) · 63043 (1) · 63044 (1) · 63048 (3) · 63052 (4) · 63053 (5) · 63057 (2) · 63066 (1) · 63076 (1) · 63078 (1) · 63082 (1) · 63086 (1) · 63088 (1) · 63091 (1) · 63103 (2) · 63295 (28) · 63308 (8) · 63621 (1) · 64421 (1) · 64462 (1) · 64480 (1) · 64484 (1) · 64491 (1) · 64492 (2) · 64494 (2) · 64495 (2) · 64597 (1) · 64629 (1) · 64634 (1) · 64636 (1) · 64643 (2) · 64645 (1) · 64727 (12*) · 64778 (1) · 64783 (1) · 64787 (7) · 64832 (1) · 64837 (3) · 64859 (2) · 64872 (15) · 64874 (15) · 64876 (15) · 64901 (6) · 64902 (6) · 64913 (1) · 65757 (1) · 66990 (12) · 67225 (1) · 67320 (5) · 67331 (5) · 67332 (5) · 67334 (5) · 67335 (9) · 67340 (9) · 69990 (193)
Chapter IX (CPT 70000-79999): 27 add-on codes
70472 (5) · 74248 (2) · 74301 (1) · 74425 (4) · 74713 (1) · 75565 (4) · 75774 (0*) · 76015 (1) · 76125 (0*) · 76802 (1) · 76810 (1) · 76812 (1) · 76814 (1) · 76937 (0*) · 76979 (1) · 76983 (1) · 77001 (0*) · 77002 (72) · 77003 (14) · 77063 (1) · 77293 (2) · 77439 (2) · 78020 (1) · 78434 (2) · 78496 (1) · 78730 (1) · 78835 (2)
Chapter X (CPT 80000-89999): 22 add-on codes
80506 (1) · 81266 (1) · 81416 (1) · 81426 (1) · 81536 (1) · 82952 (1) · 86826 (1) · 87187 (2) · 87503 (1) · 87904 (1) · 88155 (13) · 88177 (2) · 88185 (1) · 88311 (7*) · 88314 (12) · 88332 (1) · 88334 (2) · 88341 (1) · 88350 (2) · 88364 (1) · 88369 (2) · 88373 (1)
Chapter XI (CPT 90000-99999): 148 add-on codes
90461 (1) · 90472 (6) · 90474 (6) · 90481 (4) · 90785 (9) · 90833 (62) · 90836 (62) · 90838 (62) · 90840 (1) · 90863 (3) · 90913 (1) · 91013 (1) · 92547 (6) · 92608 (1) · 92618 (1) · 92621 (1) · 92623 (1) · 92627 (1) · 92629 (1) · 92632 (1) · 92635 (1) · 92637 (1) · 92638 (2) · 92639 (2) · 92972 (14) · 92973 (24) · 92974 (22) · 92978 (24) · 92979 (1) · 92998 (1) · 93319 (6) · 93320 (14) · 93321 (16) · 93325 (20) · 93352 (2) · 93356 (14) · 93462 (18) · 93463 (18) · 93464 (15) · 93563 (8) · 93564 (6) · 93565 (8) · 93566 (14) · 93567 (18) · 93568 (42) · 93569 (43) · 93571 (30) · 93572 (1) · 93573 (43) · 93574 (43) · 93575 (43) · 93584 (4) · 93585 (4) · 93586 (4) · 93587 (4) · 93588 (4) · 93592 (2) · 93598 (5) · 93609 (3) · 93613 (1) · 93621 (1) · 93622 (3) · 93623 (7) · 93655 (3) · 93657 (1) · 93662 (61) · 93896 (1) · 93897 (1) · 93898 (1) · 94645 (1) · 94729 (7) · 94781 (1) · 95079 (1) · 95873 (9) · 95874 (9) · 95885 (7) · 95886 (7) · 95887 (7) · 95940 (29) · 95941 (29) · 95962 (1) · 95967 (1) · 95984 (1) · 96113 (1) · 96121 (1) · 96131 (1) · 96133 (1) · 96137 (5) · 96139 (5) · 96159 (1) · 96160 (98*) · 96161 (114*) · 96165 (1) · 96168 (1) · 96171 (1) · 96203 (1) · 96361 (5) · 96366 (4) · 96367 (5) · 96368 (7) · 96370 (1) · 96371 (1) · 96375 (5) · 96376 (4) · 96411 (2) · 96415 (1) · 96417 (1) · 96423 (1) · 96547 (68) · 96548 (68) · 96570 (3) · 96571 (4) · 96934 (1) · 96935 (1) · 96936 (1) · 97009 (1) · 97130 (1) · 97546 (1) · 97551 (1) · 97598 (1) · 97811 (2) · 97814 (2) · 98981 (1) · 99100 (0*) · 99116 (0*) · 99135 (0*) · 99140 (0*) · 99153 (3) · 99157 (2) · 99292 (1) · 99359 (1) · 99415 (9) · 99416 (1) · 99417 (11) · 99418 (6) · 99425 (1) · 99427 (1) · 99437 (1) · 99439 (1) · 99458 (1) · 99459 (23) · 99467 (1) · 99486 (1) · 99489 (1) · 99494 (2) · 99498 (1) · 99602 (1) · 99607 (2)
Chapter XIII (CPT Category III 0001T-0999T): 112 add-on codes
0054T (0*) · 0055T (0*) · 0076T (1) · 0095T (1) · 0098T (1) · 0164T (1) · 0165T (1) · 0174T (4) · 0214T (1) · 0215T (2) · 0217T (1) · 0218T (2) · 0222T (3) · 0397T (11) · 0437T (0*) · 0439T (5) · 0443T (9) · 0450T (1) · 0480T (1) · 0496T (1) · 0513T (1) · 0523T (8) · 0560T (1) · 0562T (1) · 0570T (1) · 0599T (1) · 0628T (1) · 0630T (1) · 0649T (46) · 0676T (1) · 0678T (1) · 0690T (21) · 0698T (46) · 0701T (1) · 0709T (1) · 0722T (48) · 0724T (3) · 0735T (5) · 0742T (2) · 0751T (1) · 0752T (1) · 0753T (1) · 0754T (1) · 0755T (1) · 0756T (1) · 0757T (1) · 0758T (1) · 0759T (1) · 0760T (1) · 0761T (1) · 0762T (1) · 0763T (1) · 0764T (3) · 0767T (1) · 0770T (31) · 0772T (1) · 0774T (1) · 0777T (8) · 0791T (1) · 0821T (1) · 0822T (1) · 0827T (1) · 0828T (1) · 0829T (1) · 0830T (1) · 0831T (1) · 0832T (1) · 0833T (1) · 0834T (1) · 0835T (1) · 0837T (1) · 0838T (1) · 0839T (1) · 0840T (1) · 0841T (1) · 0842T (1) · 0843T (1) · 0844T (1) · 0845T (1) · 0847T (1) · 0848T (1) · 0849T (1) · 0850T (1) · 0851T (1) · 0853T (1) · 0854T (1) · 0855T (1) · 0856T (1) · 0857T (2) · 0859T (1) · 0866T (3) · 0882T (23) · 0883T (1) · 0887T (276) · 0896T (1) · 0899T (1) · 0900T (1) · 0907T (1) · 0914T (12) · 0945T (1) · 0961T (2) · 0974T (1) · 0976T (1) · 0984T (8) · 0985T (1) · 0986T (10) · 0987T (1) · 0993T (3) · 1006T (1) · 1022T (13) · 1023T (12) · 1024T (23)
Other CPT codes (Category II, PLA and suffixed codes): 21 add-on codes
0071U (1) · 0072U (1) · 0073U (1) · 0074U (1) · 0075U (1) · 0076U (1) · 0130U (2) · 0133U (1) · 0134U (3) · 0136U (1) · 0137U (1) · 0138U (1) · 0157U (1) · 0158U (1) · 0159U (1) · 0160U (1) · 0161U (1) · 0162U (5) · 0207U (1) · 0427U (2) · 0583U (1)
Primary codes with the most add-ons
Some primary procedures accept many different add-on codes, usually because the procedure can be extended in several ways at the same session. The count is how many add-on codes list the code as an acceptable primary in the edit file.
| Primary code | Code range (policy manual chapter) | Add-on codes listing it |
|---|---|---|
| 22633 | Chapter IV (CPT 20000-29999) | 23 |
| 22630 | Chapter IV (CPT 20000-29999) | 22 |
| 22634 | Chapter IV (CPT 20000-29999) | 21 |
| 93596 | Chapter XI (CPT 90000-99999) | 21 |
| 93597 | Chapter XI (CPT 90000-99999) | 21 |
| 22532 | Chapter IV (CPT 20000-29999) | 20 |
| 22533 | Chapter IV (CPT 20000-29999) | 20 |
| 22551 | Chapter IV (CPT 20000-29999) | 20 |
| 22554 | Chapter IV (CPT 20000-29999) | 20 |
| 22556 | Chapter IV (CPT 20000-29999) | 20 |
| 22558 | Chapter IV (CPT 20000-29999) | 20 |
| 22600 | Chapter IV (CPT 20000-29999) | 20 |
| 22610 | Chapter IV (CPT 20000-29999) | 20 |
| 22612 | Chapter IV (CPT 20000-29999) | 20 |
| 93593 | Chapter XI (CPT 90000-99999) | 20 |
| 93594 | Chapter XI (CPT 90000-99999) | 20 |
| 22548 | Chapter IV (CPT 20000-29999) | 19 |
| 22552 | Chapter IV (CPT 20000-29999) | 19 |
| 22590 | Chapter IV (CPT 20000-29999) | 19 |
| 22595 | Chapter IV (CPT 20000-29999) | 19 |
| 22800 | Chapter IV (CPT 20000-29999) | 19 |
| 22802 | Chapter IV (CPT 20000-29999) | 19 |
| 22804 | Chapter IV (CPT 20000-29999) | 19 |
| 22808 | Chapter IV (CPT 20000-29999) | 19 |
| 22810 | Chapter IV (CPT 20000-29999) | 19 |
Where QuickIntell fits with add-on codes
An add-on line is paid only when an accepted primary procedure is on the claim. QuickCode supports qualified coder review before the billing handoff, where add-on and primary codes are checked together, and QuickRCM works the CARC 107 and N122 denials with human review.
Frequently asked questions
Can an add-on code be billed by itself?
Almost never. An add-on code describes work done in addition to a primary procedure by the same practitioner, so Medicare pays it only when an accepted primary code is on the claim. The manual notes rare exceptions, such as additional critical care time billed by a physician of the same specialty in the same group as the physician who billed the first hour.
What is the difference between type 1, type 2 and type 3 add-on edits?
A type 1 edit lists every acceptable primary code and contractors should not accept others. A type 2 edit lists none, so each Medicare Administrative Contractor publishes or applies its own list. A type 3 edit lists some primaries, and contractors may accept additional ones.
Is G2211 an add-on code?
Yes. G2211, the visit complexity add-on for office or outpatient and home or residence evaluation and management visits, is a type 1 add-on code: the edit file lists the visit codes it may be reported with, and on a practitioner claim it is denied when none of them is on the claim.
Which denial codes does a missing primary produce?
The remittance usually carries claim adjustment reason code 107 (the related or qualifying claim or service was not identified on this claim) with remark code N122 (add-on code cannot be billed by itself). On institutional claims the Integrated Outpatient Code Editor has edit 106 for type 1, 107 for type 2 (critical access hospital professional lines only) and 108 for type 3, applied as line item denials on the bill types its specification lists. On a standard OPPS hospital outpatient claim (bill type 013x) only edit 106 applies, and only to remote mental health and software-as-a-service add-on codes.
How often does the add-on code edit file change?
CMS publishes the complete file before January 1 each year, when most new add-on codes take effect, and posts a complete replacement in April, July or October only when something changes.
For a one-paragraph definition see the add-on code glossary entry; for the other edit types see the NCCI edits reference.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-10. Verify against the primary file before billing or contracting decisions. The reference methodology explains how each figure is computed from these files.
- NCCI Add-On Code edits, effective 2026-10-01Version 2026 Q4 · effective 2026-10-01 · file AOC_V2026Q4-F-MCR.xlsxSHA-256 eabb519623134549…
- HCPCS Level II alpha-numeric file, October 2026Version October 2026 · effective 2026-10-01 · file HCPC2026_OCT_ANWEB_09232026.txtSHA-256 c25240c63108756d…
Disclaimer
Reproduced from the CMS add-on code edit file as an operational reference; contractors define the primaries for type 2 codes and may add primaries for type 3 codes. HCPCS Level II descriptors are public; CPT codes appear as bare numbers. Not legal, clinical or billing advice.
Found a figure that does not match the CMS file? Report a data correction with the CMS file and the value you expected; the request reaches the editorial team through the contact form.