Right to Buy Calculator — Before the Rules Change Again

Under the rules still in force as of 2026, houses start with a 35% discount after 3 years of qualifying tenancy, rising 1% for each additional year, up to a maximum of 70%. Flats start at 50%, rising 2% per additional year, to the same 70% maximum. Whichever percentage applies, it's also capped by a regional cash limit — you receive whichever figure, the percentage calculation or the cash cap, gives the lower discount.

Running your own numbers through a proper Right to Buy calculator matters more this year than usual, because the scheme itself is genuinely in transition. A figure that looked right based on last year's rules, or on a friend's experience from a few years back, could now be meaningfully wrong given how much the cash cap and percentage structure have already changed, and how much further they're set to change again.

Right to Buy is a genuinely rare example of a UK homeownership scheme changing meaningfully within a single calendar year, rather than staying broadly stable and only adjusting figures annually. The November 2024 cash cap cut alone reduced the maximum discount by well over £80,000 in some regions. The further reform confirmed for 2026/27 would cut it again, this time by restricting the maximum percentage itself from 70% down to just 15%.

This matters because eligible tenants weighing whether to apply are effectively working against a moving target. A Right to Buy calculator that shows both the current-rules figure and the reformed figure side by side, rather than just one static number, makes the genuine size of that gap visible — and helps eligible tenants judge whether applying under the existing, more generous rules, while they're still in force, is worth prioritising.

This reform is confirmed by government but not yet in force — expected to take effect later in 2026/27, once Parliamentary time allows, with no strict implementation date yet set. Newly built social and affordable homes will also be exempt from Right to Buy for 35 years once built, to protect new housing stock.

The government's stated reasoning centres on protecting the country's dwindling social housing stock, giving councils more room to rebuild and replace homes sold under the scheme, and allowing local authorities to retain all sale receipts rather than a portion being returned centrally. For longstanding tenants who genuinely can't yet meet even the current 3-year threshold, the practical effect is straightforward: by the time they do qualify, the far less generous 10-year, 15%-maximum regime is very likely to already be in force.

The maximum cash discount was cut sharply on 21 November 2024, from £102,400 (outside London) and £136,400 (London) down to a much lower range of roughly £16,000 to £38,000, varying by region. This single change already made Right to Buy considerably less generous, well before the further percentage-based reforms were confirmed.

The exact figure genuinely depends on your specific local authority, since the cap is set regionally rather than as a single national number. Some higher-value areas retain a cap closer to the £38,000 upper end, while many parts of England, particularly outside London and the South East, sit closer to the £16,000 lower end. Checking your own council's published figure, rather than assuming a generic national average, is worth doing before relying on this calculator's result as a precise number.

If you sell within 5 years of buying, you must repay a proportion of the discount received, on this tapered basis. This is a genuinely important factor for lenders to consider, and one worth planning around if a sale might be needed sooner than expected.

This repayment obligation is calculated against the discount's original cash value, adjusted to reflect any change in the property's value since the original purchase, rather than as a fixed proportion of the sale price.

In practice this means a genuinely rising local property market could increase the amount repayable beyond the simple percentage shown in the table above. Running the numbers through a Right to Buy calculator before committing helps make this risk concrete rather than abstract.

Under current rules, you need at least 3 years as a public sector tenant, which doesn't need to be with the same landlord or in the same property. You must also have no serious debt or legal issues, no outstanding possession order, and no history of tenancy fraud.

Some properties are exempt from Right to Buy entirely, and your landlord can confirm your specific eligibility, including whether you have a Preserved Right to Buy if your tenancy transferred from a council to a housing association. A quick check with a Right to Buy calculator alongside your landlord's confirmation gives you both the numbers and the eligibility picture together.

With the reform confirmed but not yet in force, tenants who are currently eligible under the existing rules face a genuinely time-limited window. The November 2024 cash cap cut already triggered a spike in applications from tenants racing to beat that deadline, and a similar rush is widely expected as awareness of the confirmed 2026/27 changes grows. If you currently qualify and the numbers work for your circumstances, applying sooner rather than later is worth genuinely serious consideration.

It's worth being realistic about how long the application process itself can take. From submitting the RTB1 form to actually completing the purchase, the process commonly takes several months, involving a formal valuation, a response from your landlord, and often a period of negotiation if you disagree with the valuation given. Starting the process well before any reform's implementation date, rather than at the last possible moment, gives genuinely more room to complete under the current, more favourable rules.

Here's how the numbers work through a real Right to Buy calculator scenario. A £220,000 house, 10 years of tenancy.

Under current rules: 35% + (7 × 1%) = 42% calculated discount, or £92,400. But this is capped at a regional cash limit of £16,000, which is lower, so the actual discount is £16,000, giving a purchase price of £204,000.

Under the confirmed reform, with the qualifying period raised to 10 years, this tenant would just reach eligibility. The discount works out at 5% + (0 × 1%) = 5%, or £11,000 — still below the cash cap, so the discount stays at roughly £11,000. That's a genuine reduction of £5,000 purely from the reformed percentage structure, before even accounting for the extra years now needed to reach that lower starting point.

Official sources & further reading: check your eligibility at GOV.UK, and read general guidance at MoneyHelper. Model the mortgage you'd need with our mortgage affordability calculator, or check your loan-to-value with our LTV calculator.