These are errors and rejects every filer can get when sending information returns to IRIS, whether through the free IRIS Taxpayer Portal or through filing software. IRIS reports each one on the acknowledgment by rule number.
Form 1099-INT business rules
Besides the rules on this page, IRIS checks the rules every form shares, such as SHAREDIRFORM014 (payee name and TIN); those are on the cross-form error code pages. The IRIS Taxpayer Portal also takes Form 1099-INT as a CSV upload, using the IRS template for the form.
In the tax year 2026 rule set: 3 report error and reject over the threshold. A reject stops the submission; a report error is accepted with errors and counts as filed; past an unpublished threshold, report errors reject the submission. The descriptions are our own summaries; your acknowledgment gives the rule number.
| Rule | Severity | What it checks |
|---|---|---|
| F1099INT001 | Report error, reject over threshold | Federal income tax withheld looks too high compared with the income amounts reported on the form. |
| F1099INT002_001 | Report error, reject over threshold | Specified private activity bond interest, if reported, cannot be more than tax-exempt interest. |
| F1099INT004 | Report error, reject over threshold | If foreign tax paid is reported, the foreign country or U.S. possession is required. |
Elements of Form1099INTDetail
Each Form 1099-INT return is one Form1099INTDetail record in a submission of group 1. The table lists its 27 elements in schema order for tax year 2026: whether each is required, and the format IRIS accepts. Element names are the ones the IRS uses in its IRIS ATS examples and Publication 5718; the IRS revises the schema each year. A FIRE filer converting a Pub 1220 file finds the field-by-field mapping in the Pub 1220 to IRIS crosswalk.
| Element | Required | Format |
|---|---|---|
TaxYr | Required | Four-digit year |
RecordId | Required | Whole number, up to 8 digits |
IssuerOfficeCd | Optional | Exactly 4 characters |
CFSFElectionStateCd | Optional | Two-letter state or territory code |
VoidInd | Required | 1 (yes) or 0 (no) |
CorrectedInd | Required | 1 (yes) or 0 (no) |
PrevSubmittedRecRecipientGrp | Optional | Group of elements |
RecipientDetail | Required | Group of elements |
RecipientAccountNum | Optional | Text, up to 30 characters |
SecondTINNoticeInd | Required | 1 (yes) or 0 (no) |
FATCAFilingRequirementInd | Required | 1 (yes) or 0 (no) |
PayerRoutingTransitNum | Optional | 9-digit routing number |
InterestIncomeAmt | Optional | Amount, zero or more, up to 2 decimal places |
EarlyWithdrawalPenaltyAmt | Optional | Amount, zero or more, up to 2 decimal places |
USSavingsBondsTreasObligIntAmt | Optional | Amount, zero or more, up to 2 decimal places |
FederalIncomeTaxWithheldAmt | Optional | Amount, zero or more, up to 2 decimal places |
InvestmentExpenseAmt | Optional | Amount, zero or more, up to 2 decimal places |
ForeignTaxesPaidAmt | Optional | Amount, zero or more, up to 2 decimal places |
ForeignCountryOrUSPossessionCd | Optional | IRS two-letter country code |
TaxExemptInterestAmt | Optional | Amount, zero or more, up to 2 decimal places |
SpcfdPrvtActyBondInterestAmt | Optional | Amount, zero or more, up to 2 decimal places |
MarketDiscountAmt | Optional | Amount, zero or more, up to 2 decimal places |
BondPremiumAmt | Optional | Amount, zero or more, up to 2 decimal places |
TreasuryObligBondPremiumAmt | Optional | Amount, zero or more, up to 2 decimal places |
TaxExemptBondPremiumAmt | Optional | Amount, zero or more, up to 2 decimal places |
TaxExemptTaxCreditBondCUSIPNum | Optional | Text, up to 9 characters |
StateLocalTaxGrp | Optional, repeats | Group of elements |