Private residence relief calculator
Private residence relief calculator: enter the months the property was your only or main home before the final period, and the calculator below splits the gain into the exempt share and the chargeable share. It adds the final period the law counts as occupation whether or not you lived there, works out the fraction, then taxes only what is left.
The relief is the difference between no tax and a full rate bill. A home lived in for part of the ownership period pays capital gains tax on the other part, and only the chargeable remainder meets the 18% and 24% rates and the £3,000 annual exempt amount.
The relief
How the exempt fraction is built
A property that was your only or main home throughout the whole period of ownership is fully exempt. The calculator carries a main-home switch for that case, and it produces no chargeable gain at all.
A home lived in for part of the period is exempt for a time fraction. The numerator is the months the property was your main home before the final period, plus the final period of ownership, which counts as occupation in any event. Months you lived there inside the final period are already in the final period, so they are never counted twice. The denominator is the complete months of ownership. The fraction never exceeds the whole gain, and a loss on a part-period home is restricted by the same fraction.
The final period has shortened over the years. A disposal today counts the last 9 months of ownership as occupation. Disposals in earlier eras counted more, and the calculator picks the figure from the sale date automatically.
Some absences still count as living there, and the months-lived input is where they belong: add any months the law deems occupancy to the months you physically occupied the home, stopping where the final period begins. The input covers plain occupation and the deemed absences stated in HMRC's helpsheet; it does not price lettings relief.
The final period counted as occupation, by disposal date
| Disposal date | Final period |
|---|---|
| From 6 April 2020 | 9 months |
| 6 April 2014 to 5 April 2020 | 18 months |
| 10 December 2003 to 5 April 2014 | 36 months |
| Before 10 December 2003 | 12 months |
Worked example
Seven years in, three years let: £4,320 of CGT
You buy a house on 1 September 2016 for £220,000 and complete its sale on 1 September 2026 for £340,000, a gain of £120,000. You lived in it as your main home for 84 months, then moved out and let the whole property and moved elsewhere for the remaining 36 months.
Ownership is 120 complete months. The exempt numerator is 84 months lived in plus the 9-month final period: 93 of 120 months, or 77.5% of the gain. That removes £93,000, leaving £27,000 chargeable. The £3,000 annual exempt amount comes off next, leaving £24,000.
On an income of £20,000 the whole basic-rate band is unused, so the entire £24,000 is charged at 18%. The tax on the disposal is £4,320, on a gain of £120,000, because 77.5% of it never became chargeable.
One part-period home sale in 2026/27
| Step | Amount |
|---|---|
| Sale proceeds | £340,000 |
| Purchase price | £220,000 |
| Capital gain | £120,000 |
| Private residence relief (93/120 months) | −£93,000 |
| Chargeable gain | £27,000 |
| Annual exempt amount | −£3,000 |
| Taxed at 18%, income £20,000 | £24,000 |
| Tax on the disposal | £4,320 |
Letting and absences
Months that count and months that do not
Letting the whole property while you lived somewhere else ends the relief for those months. They sit on the chargeable side of the fraction, and only the final period can claw any of them back.
Letting part of the home while still living in the rest is different: the home can remain the main home, and the let part may attract lettings relief of its own. This calculator does not compute lettings relief, and nothing on this page prices it. Where it applies, it comes off the chargeable gain on top of the fraction.
The final period stretches to 36 months for people who moved into a care home or became disabled. The calculator applies the standard 9-month period.
- The fraction works in complete months. Part months at either end of a period do not count.
- Two homes at once means nominating one as the main home; only the nominated months count.
- Marriage or civil partnership allows one main home between two people, not one each.
Questions
Frequently asked questions
How is private residence relief calculated?
As a fraction of the gain: the months the property was your only or main home, plus the final 9 months of ownership, over the complete months you owned it. The calculator computes the months of ownership from your dates, so you only enter the months lived in before the final period.
What is the final period?
The stretch at the end of ownership that counts as occupation in any event. It is 9 months for disposals from 6 April 2020, and it was longer for earlier disposals. It is added to your lived-in months, capped at the total months owned.
I let the property for part of the time I owned it. What happens?
The let months are chargeable months, except any covered by the final period. In the worked example, 36 months were let and only 27 of them stayed chargeable after the final 9 months were counted as occupation.
What is lettings relief and does the calculator apply it?
Letting relief can reduce the chargeable gain where part of the home was let while you lived in the rest. This calculator does not compute it, and where it applies it comes off after the residence fraction.
Does private residence relief apply to a loss?
Yes, in the same proportion. A loss on a part-period home is restricted by the exempt fraction, so only the chargeable share of the loss is an allowable capital loss.
Is the gain tax free if I lived there the whole time?
Yes. A home that was your only or main home throughout ownership is fully exempt. Tick the main-home switch on the property row and the calculator produces no chargeable gain.
Sources
Where these figures come from
Also on capitalgainstax.net