To fill out a money order for child support, write the State Disbursement Unit (or whichever payee your court order names) on the “Pay To” line, put your child support case number on the memo line, enter your full name and current address as the purchaser, and sign the front. Those four entries, done correctly and in ink, are what makes the payment post to your account instead of sitting in limbo.
Every field matters more than it does on a personal check, because a money order made out wrong can’t be traced back to you the way a bounced check can. Fill it out at the counter, before you leave the store or post office. A blank money order is essentially cash to anyone who finds it.
The Payee Line
In most child support cases, the payee is not your co-parent. Federal law requires each state to run a State Disbursement Unit that collects and distributes child support payments handled through the state’s child support agency.1Office of the Law Revision Counsel. 42 USC 654b – Collection and Disbursement of Support Payments The payee line on your money order should read exactly what your court order or payment coupon says, which is usually the SDU or the state child support enforcement agency.
Copy the name character for character. A small variation, an abbreviation the agency doesn’t use, or a missing word can delay processing while a clerk figures out where the payment belongs. If your order routes payments through the SDU and you write your co-parent’s name instead, the payment won’t register in the system at all, and the agency may treat you as delinquent even though the money changed hands.
The Case Number
After the payee, your case number is the most important detail on the money order. Without it, the SDU has no way to match your payment to your account. Write it clearly on the memo line, which some money orders label “Payment For” or “Account Number” instead.
You’ll find the case number on your court order and on any correspondence from the child support agency. Check every digit before you drop the money order in the mail. A transposed number can route your payment to a stranger’s case, and untangling that takes weeks of phone calls.
Purchaser Name and Address
Fill in your full legal name and current mailing address in the “From” or “Purchaser” section. The agency uses these to identify you as the payer and to reach you with any questions about the payment.
If you’ve moved recently, update your address with the child support agency separately. Writing a new address on a money order does not count as a formal change of address on file.
Amount and Signature
The dollar amount is printed on the money order when the clerk sells it to you, so you don’t fill it in yourself. Confirm the printed amount matches your monthly obligation before you leave the counter. Overpayments don’t automatically credit forward to future months in every state, and underpayments can trigger enforcement action no matter how close you came to the correct figure.
Sign the front of the money order on the purchaser’s signature line. Leave the back alone. That line is reserved for the person or agency cashing it, and signing there yourself can cause the money order to be rejected.
Where to Send It
Your court order or payment coupon tells you exactly where the payment goes. For cases enforced through the state agency, the mailing address for the SDU is printed on your payment coupon.1Office of the Law Revision Counsel. 42 USC 654b – Collection and Disbursement of Support Payments Sending the money order directly to your co-parent when the order requires SDU processing is a common and costly mistake. The payment will not appear in the state’s system, and your account will show a missed month.
Some SDUs also accept in-person drop-off at local child support offices. If you’re unsure, call the agency or check its website before you mail anything. A payment sent to an outdated address can take weeks to redirect.
Include a short cover note with your name, case number, the month the payment covers, and a phone number. It isn’t required, but it gives the processing clerk a second chance to match your payment correctly if the memo line is hard to read.
Getting Proof the Payment Arrived
How you deliver the money order matters almost as much as how you fill it out. If a payment goes missing and you have no proof you sent it, you’re the one explaining a gap in your record.
Certified mail with a return receipt is the strongest option for mailed payments. The certified mail fee is $5.30, and the physical return receipt (PS Form 3811) adds $4.40, for $9.70 on top of postage.2United States Postal Service. USPS Notice 123 – January 2026 Price Change An electronic return receipt runs $2.82 if you don’t need the green card. That fee buys you a signed, dated confirmation that the agency received your envelope, which is worth far more than the cost if a payment ever gets disputed.
Hand-delivery to the child support office eliminates postal delays. Ask for a stamped receipt when you drop it off. If you’re close to a deadline, in-person delivery is the safer choice.
Keeping the Receipt
Every money order comes with a receipt or detachable stub showing the amount, date, serial number, and (for USPS money orders) a tracking number you can use to check whether it was cashed. Keep it. Store it with your payment coupon, any cover letter, and the certified mail return receipt in a dedicated folder, physical or scanned.
Hold onto these records for at least three years past the end of your child support obligation. Disputes about past payments can surface years later during a modification hearing or an arrears review. A parent with receipts for every payment is in a fundamentally different position than one relying on memory.
If the Money Order Is Lost or Stolen
A lost money order can be replaced, but the process takes time, which matters when a payment is due.
For USPS money orders, file an inquiry using PS Form 6401 at any post office. Bring your original purchase receipt, complete one form per money order, and pay a fee for each inquiry. USPS will either issue a refund 60 days or more after the money order’s issue date or provide a copy showing it was already cashed.3United States Postal Service. Money Order Inquiry – PS Form 6401 You can check inquiry status by calling 1-866-974-2733. The whole process can take up to 60 days.
Western Union money orders follow a different process. You submit a refund request online or by mail with proof of purchase, such as the original receipt with barcode or a copy of the money order. Approved refunds are processed within five business days, minus a non-refundable processing fee.4Western Union. Money Order Request Form If you’ve lost the receipt, you may still be able to file by providing a store receipt along with a police report referencing the money order number. A refund is only possible if the money order hasn’t already been cashed.
Notify the child support agency the same day you realize the money order is missing. Explain the situation, share any tracking information, and ask whether to send a replacement immediately. Waiting 60 days for a USPS refund while your account shows a missed payment invites enforcement action, so if you can afford it, send a replacement payment now and treat the eventual refund as reimbursement to yourself.
Fixing an Error After You’ve Mailed the Payment
If you realize you wrote the wrong case number, misspelled the payee, or made another mistake after the envelope is already gone, call the child support agency right away. Give them the money order serial number, the amount, the date you mailed it, and any tracking information. Agencies can often locate a payment manually and post it correctly once they know what to look for. From the agency’s side, a payment that hasn’t posted looks the same as a payment that was never made, so the sooner they know, the better.
When to Consider Skipping the Money Order
Money orders work for child support, but they aren’t the fastest option. Most state child support agencies now accept electronic payments through their online portals, and some work with third-party services. Electronic payments post faster, generate automatic records, and remove the risk of a lost envelope. If you’re using money orders because you don’t have a bank account, that’s a reasonable choice. If you’re using them out of habit, check your state’s child support agency website for the payment methods available to you.