Key self-assessment dates for the 2025/26 season

Racing income rarely arrives in a neat monthly pattern. Riding fees, prize money, retainers and sponsorship can land at different times, which makes the self-assessment calendar easy to miss until it is urgent. Putting the key dates in the diary early is one of the simplest ways to stay ahead.

This note is general information for UK self-assessment. Your own position may differ — especially if you also file in Ireland or elsewhere — so treat it as a checklist, not personal tax advice.

Dates to diary

For the 2025/26 tax year (6 April 2025 to 5 April 2026), the usual UK self-assessment rhythm still applies: register if you need to, keep records through the season, then file and pay to the normal deadlines that follow the year end.

In practice that means planning for: the online filing deadline (normally 31 January following the tax year), balancing payment on the same date where due, and any payments on account. If you pay by paper return, the earlier paper deadline still applies.

If you expect a large balancing payment — for example after a strong season or a one-off commercial deal — start estimating liability well before January. Racing professionals who wait until the return is finished often find the cash pressure arrives at the worst moment.

What to have ready

Keep a clean running record of riding fees, prize money, retainers, appearance fees and sponsorship. Separate reimbursed expenses from income. Save contracts, agent statements and bank records so year-end is reconstruction, not archaeology.

Set a tax reserve as income arrives, not after it has been spent. A private-office rhythm of quarterly check-ins makes the January deadline far less dramatic.