Metro 2 Account Type Code 18: Credit Card (Bankcard)

Specification

Code	18
Meaning	Credit Card (Bankcard)
Field	Account Type (Field 15)
Record	Base Segment
Length / position	2 chars · 84–85
Category	Revolving Accounts
CRRG reference	CRRG Exhibits 1 & 2 (Account Type Codes)

Two facts define it: it revolves, and it is general purpose rather than tied to a single merchant.
Does NOT cover a store-exclusive charge account, which is 07 even though it also revolves.
Does NOT cover a secured card backed by a deposit, which is 2A. The deposit is a material fact consumers and lenders both read from the tradeline.
Does NOT cover a card with no preset spending limit, which is 0G, because the missing Credit Limit changes how utilization must be computed.
Does NOT cover a debit card. A debit card draws on the consumer's own funds and is not credit.

1An issuer reports a general-purpose rewards card with a $12,000 limit and a revolving balance.
2A credit union reports a member bankcard where the limit was raised after an account review.
3An issuer reports a card the consumer keeps at a zero balance, so the tradeline contributes age and available credit.
4An issuer reports a card in a hardship programme with a reduced payment, carried through Account Status and Special Comment rather than a new account type.
5An issuer reports a charged-off card and continues reporting the balance owed while the Date of First Delinquency stays anchored.

Populate Credit Limit every cycle with the current limit. This single field drives revolving utilization across every major scoring model.
Update Highest Credit when a new high balance is reached, and never lower it to the current balance.
Report the contractual minimum payment in Scheduled Monthly Payment Amount and the amount received in Actual Payment Amount.
Report authorized users through ECOA and a J1 or J2 segment rather than opening separate tradelines.
Do not stop reporting an open card because the balance is zero. Silence is read as closure.

A file can be structurally valid and still be wrong. These are the cross-field conditions Account Type Code 18 has to satisfy.

Portfolio Type must be R (Revolving). Terms Duration is reported as REV, never as a month count.
Portfolio Type R expects a populated Credit Limit. A bankcard tradeline with a zero or missing limit forces models onto Highest Credit and systematically overstates the consumer's utilization.
Current Balance above Credit Limit is legitimate but flagged. Confirm you are reporting the current limit before treating it as an over-limit condition.
Terms Frequency is M on a monthly-billed card.
After a charge-off, Account Type stays 18 while Account Status changes, and Date of First Delinquency must be populated and must not be re-aged.
If the receivable is later sold, the buyer reports under 0C with the K1 segment naming you, and your tradeline reports Account Status 05 with a zero balance.