To claim the Iowa corn checkoff refund on Form R18, mail the completed form along with your settlement sheets or purchase invoices to the Iowa Corn Promotion Board within 60 days of the date the assessment was deducted from your sale.1Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment2Iowa Corn. Iowa Corn Checkoff Market Development3Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment Miss the 60-day window and the money is gone for that sale.
Where to Get the Form
Iowa law requires every first purchaser — elevators, grain dealers, and processors — to keep blank Form R18 applications available for producers who ask.3Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment Ask at the elevator where you delivered your corn. You can also request one directly from the Iowa Corn Promotion Board at (515) 225-9242.4Iowa Corn. Contact Iowa Corn
What to Attach as Proof
The statute requires proof that the assessment was actually paid, and that proof is a duplicate or certified copy of the purchase invoice from the first purchaser.1Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment Pull the settlement sheet for every sale you want refunded and check that each one shows your name as the seller, the date of sale, the bushels sold, and the assessment amount deducted. If any of that is missing, get a corrected copy from the elevator before you file. An application without adequate proof will be delayed or denied.
Filling Out the Form
Enter your full legal name, or your farm entity’s name if the corn was sold under a business, and the mailing address where the check should go. Add up the bushels and the assessment dollars across all the settlements you’re attaching, and enter those totals on the form. Every field matters; blanks cause delays.
Sign and date the application. Your signature certifies that the figures are accurate and the assessments were paid. If a partner or officer is signing for a partnership or corporation, that person should have authority to act for the entity. Photocopy the completed form and every attached invoice before the envelope leaves your hands.
Mailing the Application
Send Form R18 and the attached proof to:
Iowa Corn Promotion Board
5505 NW 88th Street
Johnston, IA 501314Iowa Corn. Contact Iowa Corn
The 60-Day Deadline
The 60-day clock runs from the date the assessment was deducted, which is the sale date on your settlement sheet.1Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment Each sale has its own deadline, so if you sell corn on several different dates, filing after each one is safer than batching your requests and letting the oldest sales run out of time.
Locking In Your Postmark
Since December 2025, USPS applies postmarks when mail reaches automated processing rather than when the carrier first picks it up, a gap that can run one to three days.5Internal Revenue Service. New U.S. Postal Service Rules Could Affect Whether Your Tax Filing Is Considered On Time Dropping the envelope in a collection box the night before your deadline is a real risk. Send it Certified Mail at a post office counter instead. A postal employee stamps the certified receipt on the spot, and that receipt is your proof of the mailing date if the board ever questions your timing.6eCFR. 26 CFR 301.7502-1 – Timely Mailing of Documents and Payments Private postage meters and online-printed labels are not accepted as postmark proof.
After You File
Iowa law gives the board 30 days from the date it receives your application to send the refund.3Iowa Legislature. Iowa Code 185C.27 – Refund of Assessment Staff will match your figures against sales records reported by the first purchaser. If bushel counts, dates, or an invoice don’t line up, expect a call for clarification, which pushes the timeline out. Confirm your mailing address is current before you file. A returned check adds weeks and requires you to chase the board for a reissue.
Tax Treatment of the Refund
If you deducted the checkoff as a farm business expense on your federal return, the refund is reportable income in the year you receive it. The IRS treats agricultural payments, including state checkoff refunds, as reportable on Form 1099-G.7Internal Revenue Service. Instructions for Form 1099-G The Iowa Corn Promotion Board may send you a 1099-G if the refund meets federal reporting thresholds. Even if no form arrives, account for the refund on your Schedule F. Keep your copy of Form R18, the settlement sheets, and the certified mail receipt with your farm records.8Internal Revenue Service. Recordkeeping