Metro 2 Special Comment Code AC: Interest-Only Payments

Specification

Code	AC
Meaning	Interest-Only Payments
Field	Special Comment (Field 31)
Record	Base Segment
Length / position	2 chars · 213–214
Category	Hardship, Workout and Payment Plans
CRRG reference	CRRG Exhibits 6 & 7 (Special Comment Codes)

The source's stated purpose is a workout plan: the payment has been reduced to interest only to keep the borrower performing.
AC explains why the Current Balance is not falling. A balance that stays flat while payments arrive on time is exactly what interest-only performance looks like.
AC does NOT mean the account is delinquent. A borrower meeting an interest-only obligation is meeting the obligation that currently applies.
In this library, AC means interest-only payments. A conflicting in-repo list labels AC "Account closed by consumer"; that reading is not used here, and the closure meaning belongs to AP.
AC is temporary by nature. When principal amortization resumes, the comment comes off.

1A commercial lender drops a struggling borrower to interest-only for six months while the business stabilizes.
2A mortgage servicer places a borrower on an interest-only workout while a permanent modification is evaluated.
3A credit union reduces payments on a home-equity line to the interest portion during a documented hardship.
4An equipment lender accepts interest-only payments for two quarters rather than repossessing.

Report AC only for the cycles the interest-only structure is actually in effect.
Set Scheduled Monthly Payment to the interest-only amount so the payment expectation on the report matches the arrangement.
Remove the comment in the first file after full amortization resumes.
Do not use AC for a loan that is contractually interest-only from origination and performing as designed; this comment describes a workout, not a product feature.
If the interest-only structure was made permanent by a contract change, CN is the accurate comment from that cycle forward.

A file can be structurally valid and still be wrong. These are the cross-field conditions Special Comment Code AC has to satisfy.

Scheduled Monthly Payment should equal the interest-only amount required during the workout, not the original amortizing payment.
Current Balance holding flat cycle over cycle is expected and consistent with this comment; it should not be treated as a stale-balance defect.
Amount Past Due is measured against the interest-only requirement while the arrangement is in force.
Terms Duration and Terms Frequency normally stay at contractual values unless the contract itself was amended, in which case CN applies.
Date of First Delinquency is unaffected by moving to interest-only payments.