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Error code

MW — Maximum weeks passed since initial service was paid

Time window passed

Too many weeks have passed since the initial service in the series was paid, so this service falls outside the window.

What to do: Check the code's listing for its time window and the date the initial service was paid.

Code
MW
Description
Maximum weeks passed since initial service was paid

Explanation

Updated October 26, 2026

MW means too many weeks have passed since the first service in a series was paid. Check the code's time window.

What it means

MW means the maximum number of weeks has passed since the initial service was paid. Some services are paid only within a set time after an initial service, and this one fell outside that window.

How to fix it

  1. Check the fee code's listing in the Schedule of Benefits for a time window after an initial service.
  2. Check the date the initial service was paid.
  3. If you believe the decision is wrong, send a Remittance Advice Inquiry (RAI) through eSubmit, or on form 0918-84, within 7 months of the RA date, with supporting details.

Don't resubmit if

  • The service fell outside the allowed window.
  • The line is already on your RA. Question it with an RAI, not a new claim.

How APEX handles it

APEX reads your error reports and remittance advice from MCEDT and lists claims rejected with this code in its Correction Centre for you to correct and resubmit. See how APEX works · Pricing

Related codes: MY, H3, H5

Sources