Self assessment deadlines and penalties for landlords

The dates are fixed and the penalties escalate. Knowing the calendar and the payment on account rule avoids most of the cost.

4 min read · Updated 21 August 2026

Overview

Rental profit is reported on the property pages of a self assessment return. Registration is required by the fifth of October following the tax year in which the income first arose. Online returns are due by the thirty first of January after the tax year ends, and any balancing payment is due the same day. Payments on account fall due on the thirty first of January and the thirty first of July where the previous liability was large enough.

Why it matters

Late filing penalties start immediately and grow, and interest on late payment runs from the due date. None of it is discretionary, so the calendar is the cheapest compliance tool you have.

Legal requirements

Register for self assessment by the fifth of October following the relevant tax year.
Online returns and balancing payments are due by the thirty first of January.
Payments on account are due in January and July where the liability threshold is met.
Records supporting the return must be kept for at least five years after the filing deadline.

Common mistakes

Forgetting the July payment on account and treating January as the only deadline.
Not registering in the first year of letting because the profit was small.
Claiming mortgage interest as a full expense instead of the basic rate tax reducer.
Missing rent received in the final days of the tax year.

Practical guidance

Diarise the fifth of October, the thirty first of January and the thirty first of July.
Set aside tax monthly as a percentage of net rent rather than facing a lump sum.
Reconcile the rent account to the bank statement every month.
File early, because the calculation tells you what to save without obliging you to pay sooner.

How penalties escalate

A day late triggers a fixed penalty even where no tax is due. After three months daily penalties can accrue, with further percentage based penalties at six and twelve months. Late payment carries separate penalties plus interest. Reasonable excuse appeals succeed occasionally, usually for serious illness or bereavement, and almost never for being busy or for software difficulties discovered on the deadline day.

Correcting an error

You can amend a return within the normal amendment window. Where an error is older, HMRC has a disclosure route and using it voluntarily reduces penalties significantly compared with being discovered. Landlords who realise they have never declared rental income should take advice and use the let property disclosure route rather than hoping the position resolves itself.

Frequently asked questions

Do I need to file if I made a loss?

Usually yes, and it is worth doing. Declared rental losses can be carried forward against future rental profits, but only if they are reported.

What are payments on account?

Advance payments towards the next year's liability, each usually half of the previous year's tax, due in January and July.

How long should I keep records?

At least five years after the thirty first of January filing deadline for that tax year, and longer where a property may later be sold.

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This guide is general information for UK landlords and letting agents, not legal advice. Rules differ across England, Wales, Scotland and Northern Ireland — check your local requirements or take advice before acting.