Midwest · IA

How to file Iowa sales tax

2026 due dates, filing frequencies, form 32-028, and official filing resources.

  • State return: 32-028
  • Monthly returns due: Last day of the month following the period
  • Filing frequencies: Monthly, Annual

When is Iowa sales tax due?

Monthly Iowa sales tax returns are due the last day of the month following the period. When a due date lands on a weekend or federal holiday it moves to the next business day; the 2026 calendar on this page already applies that adjustment.

Iowa sales tax due dates for 2026

Every date below comes from the state's published deadline rule (dataset 2026.07.0) and is already moved to the next business day when it lands on a weekend or federal holiday. Your account's assigned filing frequency decides which table applies.

Monthly Iowa sales tax due dates

Rule: Last day of the month following the period.

PeriodPeriod endsReturn due
January 2026Jan 31, 2026Mar 2, 2026 (moved: 2026-02-28 falls on a Saturday)
February 2026Feb 28, 2026Mar 31, 2026
March 2026Mar 31, 2026Apr 30, 2026
April 2026Apr 30, 2026Jun 1, 2026 (moved: 2026-05-31 falls on a Sunday)
May 2026May 31, 2026Jun 30, 2026
June 2026Jun 30, 2026Jul 31, 2026
July 2026Jul 31, 2026Aug 31, 2026
August 2026Aug 31, 2026Sep 30, 2026
September 2026Sep 30, 2026Nov 2, 2026 (moved: 2026-10-31 falls on a Saturday)
October 2026Oct 31, 2026Nov 30, 2026
November 2026Nov 30, 2026Dec 31, 2026
December 2026Dec 31, 2026Feb 1, 2027 (moved: 2027-01-31 falls on a Sunday)

Annual Iowa sales tax due dates

Rule: January 31 following the calendar year.

PeriodPeriod endsReturn due
Calendar year 2026Dec 31, 2026Feb 1, 2027 (moved: 2027-01-31 falls on a Sunday)

Iowa filing notes

  • Iowa offers only monthly and annual filing (quarterly was eliminated July 2022); monthly filers must file and pay via GovConnectIowa.

Return and form

The principal repository-tracked return is 32-028. Paper eligibility is taxpayer-specific; electronic filing or a waiver may control.

Tracked form version: 32-028a (08/28/2025)

Paper filing posture: taxpayer specific

Official Iowa filing resources

File Iowa sales tax from reviewed data, not spreadsheets

Prophit.ai tracks every Iowa due date above inside the return workspace, builds the period from your transaction data, and produces worksheet for portal entry that a reviewer approves before anything is submitted.

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Workflow support does not by itself establish registration, filing authority, credentials, agency acceptance, or tax advice. Confirm your assigned filing frequency with the state.

Iowa sales tax filing questions

When is Iowa sales tax due?

Monthly Iowa sales tax returns are due the last day of the month following the period. When a due date lands on a weekend or federal holiday it moves to the next business day; the 2026 calendar on this page already applies that adjustment.

How often do you file sales tax in Iowa?

Iowa assigns a filing frequency to each account. The published cadences are monthly and annual filing; the state assigns the frequency based on tax volume and notifies the account, so confirm the assigned basis before relying on a calendar.

What form is used to file Iowa sales tax?

The Iowa return tracked here is 32-028. The principal repository-tracked return is 32-028. Paper eligibility is taxpayer-specific; electronic filing or a waiver may control.

What happens if a Iowa due date falls on a weekend or holiday?

The due date moves to the next business day. In 2026, 5 of the Iowa due dates listed on this page are adjusted for a weekend or federal holiday; each adjusted date is marked in the calendar.

Can Iowa sales tax be filed on paper?

Paper filing posture tracked for Iowa: taxpayer specific. The principal repository-tracked return is 32-028. Paper eligibility is taxpayer-specific; electronic filing or a waiver may control.