Multiple procedure indicator 2: 100 percent, then 50.

The field

The Multiple Procedure (Modifier 51) indicator is at position 35 of the payment policy indicator file (Chapter 23, section 50.6); Chapter 12 calls it Field 21. It says which payment adjustment rule applies when more than one procedure is reported for the same patient on the same day. The CMS booklet notes that surgeries subject to the standard multiple surgery rules show an indicator of 2 in the Medicare PFS look-up tool.

All the values

• 0: no adjustment; pay the lower of the actual charge or the fee schedule amount.
• 1: the older standard rules: 100, 50, 25, 25, 25 percent, then by report.
• 2: the standard rules: 100 percent for the highest-valued procedure, 50 percent for each of the second through fifth, then by report.
• 3: special rules for multiple endoscopies in the same family.
• 4: imaging reductions (50 percent of the TC from July 1, 2010; 5 percent of the PC from January 1, 2017).
• 5: therapy practice expense reduction (50 percent from April 1, 2013).
• 6 and 7: 25 percent TC reduction for cardiovascular and 20 percent for ophthalmology diagnostics, from January 1, 2013.
• 9: the concept does not apply.

How indicator 2 is applied

Rank the procedures by Medicare fee schedule amount, highest first. The ranking uses the approved fee schedule amount, not the submitted charge, so the major surgery is not necessarily the one with the largest bill. Pay the lower of the billed amount or 100 percent for the first, and 50 percent for the second through fifth. If more than five are billed, the sixth and later are paid by report, never below 50 percent. Equal values are ranked by dollars billed. Round to the nearest cent (Chapter 12, section 40.6).

Billing

Report the more major procedure without modifier 51 and the additional procedures with modifier 51. When two physicians each perform a distinctly different, unrelated surgery the same day, the multiple surgery rules may not be appropriate, and modifier 51 is used only if one surgeon individually performs several.

Special rules that change the answer

For endoscopies with indicator 3, CMS pays the full value of the highest-valued endoscopy plus the difference between the next endoscopy and the shared base endoscopy. Bilateral procedures are priced at 150 percent first and then ranked. Where a site-of-service adjustment applies, it is made before the multiple surgery adjustment.

Worked example (hypothetical)

Three procedures with fee schedule amounts of $1,000, $600 and $300 and indicator 2: $1,000 + $300 + $150 = $1,450 against a full-price sum of $1,900. The calculator reproduces this and shows the "by report" line when six or more are entered. Where the row said "50 percent rule", the 50 percent applies to the second through fifth procedures only.

FAQ

What does multiple procedure indicator 2 mean?

The standard multiple surgery rules apply: rank by fee schedule amount, pay 100 percent for the highest, and 50 percent for each of the second through fifth.

How are procedures ranked?

By the Medicare fee schedule amount, highest first, not by the amount the provider billed.

What happens after five procedures?

The sixth and later are suspended for review and paid by report, and for indicator 2 the by-report payment should never be lower than 50 percent.

Does modifier 51 go on every procedure?

No. The more major procedure is reported without modifier 51 and additional procedures by the same surgeon on the same day carry it.

What is multiple procedure indicator 0?

No payment adjustment rules for multiple procedures apply, and payment is the lower of the actual charge or the fee schedule amount.

Sources

Retrieved 2026-11-02 from the CMS documents below. Indicator meanings are paraphrased from the CMS definitions; no AMA CPT descriptors are reproduced. CMS revises the fee schedule and its manuals, so check the current text.

• CMS: Medicare Claims Processing Manual, Chapter 23, Fee Schedule Administration and Coding Requirements (Rev. 13701, issued 06-16-26): section 50.6, Multiple Procedure (Modifier 51) Indicator values 0-9 (retrieved 2026-11-02).
• CMS: Medicare Claims Processing Manual, Chapter 12, Physicians/Nonphysician Practitioners (Rev. 13753, issued 05-07-26): section 40.6, claims for multiple surgeries (retrieved 2026-11-02).
• CMS: MLN907166, Global Surgery booklet (December 2025): Multiple Surgeries (retrieved 2026-11-02).