MTD for Income Tax

How it works (it’s simpler than you think)

Keep using your spreadsheet; our app sends your totals to HMRC each quarter. At year end you confirm everything with a final declaration — your digital Self Assessment return.

ITSA MTD app icon HMRC MTD Ready logo

The year at a glance

Quarterly updates
Send a simple summary of income & expenses. From 2025–26 these are cumulative — your latest totals replace the last.
Year-end adjustments & allowances
Apply things like losses and capital allowances so figures match tax rules.
Final declaration
Your digital Self Assessment return (with the final tax calculation) — confirm all sources and submit.

Why “cumulative”? If you tweak figures later, just submit again — the new total replaces the previous one, so the latest update is what counts.

What you’ll use

  • Your spreadsheet — we provide a secure digital link to HMRC (classic bridging).
  • macOS 13+ today; iPhone & iPad coming soon.
  • View an estimated tax calculation after updates.

Deadlines

  • Each update is due one month after the period ends.
  • Default quarters apply; some can elect calendar quarters before the first update.
  • The app shows your live obligations and reminders.

Other income you may add before the final declaration

To complete your final calculation you may also include:

  • Employment (PAYE data appears from HMRC; you can amend at year end if needed).
  • Dividends, savings, pensions, capital gains, other income — supported progressively after launch.

For Agents

If you’re an accountant or tax agent, we’ve got you covered too.

Learn about agent features

HMRC campaign graphic: Tax is changing in April 2026
Tax is changing in April 2026

From the 2025–26 year onward, you’ll send quarterly updates and a final declaration via software. See HMRC’s official campaign for who needs to join and what’s changing.

Visit the MTD campaign site

FAQs

Do I need to submit detailed transactions each quarter?

No — HMRC needs summary totals (income & expenses). Keep digital records; the app submits the totals.

What if I make a mistake mid-year?

Submit again. Updates are cumulative, so your newest totals replace earlier ones.

When do I do the final declaration?

After year end, once adjustments/allowances are in — then submit the final declaration to lock the year.

Try it early / join the beta

We’re inviting a small group willing to start MTD a little early to help refine the app:

  • Early access before public release
  • Work directly with the developer
  • Influence what we prioritise next
Email to join the beta