GL posting codes on batch tapes

Common two-character codes

Code	Conventional role
HD	Batch or account header, almost always excluded from balance accumulation
DR	Debit
CR	Credit
RV	Reversal, backs out a prior posting
IN	Interest accrual
FE	Fee
AD	Adjustment (typically uses the signed amount as-is)

The arithmetic direction associated with each code is shop-specific. On some tapes a DR adds to the running balance; on others it subtracts. Loan and asset accounts often invert the deposit-side convention. Always follow the rules defined by the task at hand rather than assuming a default.

Sign zone vs unsigned magnitude

Many tapes split a transaction amount into a sign byte (+/-) and an unsigned magnitude. Some rules use only the magnitude (the code provides direction); others combine sign and magnitude into a signed value. Read each rule carefully, mixing the two is a frequent defect.

Reconciliation checks

• One output line per active account that received a non-header posting.
• Accounts sorted ascending unless the downstream system specifies otherwise.
• Recompute one or two account totals by hand from the detail tape before trusting a full balance file.

References

• AFP / z/OS GL batch overview (IBM documentation) for shop-specific code lists
• Credit-union and bank operations manuals for control-total reconciliation workflows