Shared Ownership Calculator

Calculate the true monthly cost of shared ownership — mortgage repayments, rent on the housing association's share, and service charges. Compare with buying the property outright.

How shared ownership works

Shared ownership lets you buy a share of a property (usually 25–75%) and pay rent on the remainder to a housing association. You take out a mortgage on your share and pay a deposit based on that share value — not the full property price. This makes the deposit and mortgage much smaller than buying outright.

The trade-off is that you pay rent on the portion you don't own, typically 2.75% of its value per year. This rent usually increases annually by RPI + 0.5%, meaning costs rise over time. You can buy more of the property over time through “staircasing” — purchasing additional shares until you own 100%.

Shared ownership properties are almost always leasehold, which means service charges apply. Check the service charge level carefully — high charges can significantly increase your total monthly outgoings. Also check for any restrictions on subletting, pets, or alterations in the lease.

Frequently asked questions

Who is eligible for shared ownership?
You must be a first-time buyer (or a previous homeowner who can't afford to buy now), with a household income under £80,000 (£90,000 in London). You must not already own another property. Existing shared owners looking to move are also eligible.
What is staircasing?
Staircasing is buying additional shares of the property from the housing association. You can typically staircase in increments of 10% or more. Each staircasing transaction requires a valuation and legal fees. Once you own 100%, you stop paying rent on the unowned share.
Can I sell a shared ownership property?
Yes, but the housing association usually has first refusal — they have a period (typically 8 weeks) to find a buyer from their waiting list. If they can't find one, you can sell on the open market. If you own 100%, you can sell freely without restriction.
Does the rent on the unowned share go up?
Yes — rent typically increases by RPI (Retail Price Index) + 0.5% per year, as set out in the lease. In high-inflation years, this can mean significant increases. Some newer shared ownership leases use CPI + 1% instead. Check the lease terms carefully.

Found a shared ownership property?

Get AI analysis of any property listing — red flags, fair valuation, and neighbourhood data.

Related guides

Got a specific property in mind?

Paste any Rightmove, Zoopla, or OnTheMarket listing and get AI-powered analysis with red flags, valuation, and neighbourhood intel in 60 seconds. Your first 3 analyses are free.

Try Free Analysis

More free tools

Cookie Preferences

We use essential cookies to keep you logged in and functional cookies to remember your preferences. You can customise which cookies we use. Learn more