Shared ownership lets you buy a percentage of a property — typically between 10% and 75% — and pay subsidised rent on the remainder to a housing association. It's designed to make homeownership accessible when full purchase isn't affordable. But most buyers don't plan to stay at their initial share forever. Staircasing is the process of buying additional shares over time, eventually reaching full ownership.
Here's how it works in practice, what it costs, and when it's worth doing.
A Quick Recap on Shared Ownership
You buy a share of a new or resale shared ownership property using a mortgage (or cash) and pay rent on the housing association's remaining share. The rent is typically set at 2.75–3% of the unsold equity per year. Service charges and ground rent (where applicable) are additional.
See our leasehold flat checklist for the wider obligations that come with shared ownership, which is almost always leasehold.
What Is Staircasing?
Staircasing means purchasing additional tranches of equity in your property, reducing the housing association's share and your rent payments proportionally. There are two routes:
- Incremental staircasing — Buy tranches of at least 10% at a time, progressively increasing your ownership share.
- Full staircasing — Buy the remaining share in one transaction, reaching 100% ownership.
Under the 2021 Affordable Homes Programme model (which applies to shared ownership homes built after June 2021), you can staircase in tranches as small as 1% per year for the first 15 years. However, the standard minimum remains 10% for older leases and most resale properties — check your lease carefully.
The Minimum 10% Incremental Tranche Rule
For most shared ownership properties (especially pre-2021 stock), you must buy at least 10% of the property's full market value in each staircase transaction. You cannot buy 5% here and 3% there.
Example: If your property is worth £280,000 and you own 40%, the minimum staircase purchase is 10% × £280,000 = £28,000 (plus costs).
The RICS Valuation Requirement
Every staircase — incremental or full — requires a RICS-registered surveyor to value the property. The housing association uses this valuation to set the price of the share you're buying. You commission and pay for the valuation.
| Item | Detail |
|---|---|
| Valuation cost | £300–£500 (depending on property size and location) |
| Valuation validity | 3 months — if you don't complete within this window, you need a new one |
| Who must instruct | The buyer (you), from a RICS-registered firm |
If you think the valuation is too high, you can challenge it by commissioning a second independent RICS valuation. If there's a dispute, a third valuer may be appointed. This adds time and cost but is your right.
Housing Association Right of First Refusal
On older leases (generally pre-2021 Affordable Homes Programme), the housing association may have a right of first refusal — meaning if you try to sell your share outright, they can buy it back at the independently valued price before it goes to the open market. This lasts for a set period (often 21 years from first sale in older leases).
This doesn't affect staircasing — it applies to sales. But it's worth knowing because it affects your exit options if you decide to sell rather than staircase.
Costs Per Staircase Transaction
| Cost | Typical Amount |
|---|---|
| RICS valuation | £300–£500 |
| Solicitor / conveyancer fees | £700–£2,000 |
| Mortgage arrangement fee (if remortgaging) | £0–£999 |
| Land Registry fee | £20–£295 (based on share value) |
| Total per staircase | £1,000–£2,500 |
These costs repeat every time you staircase. If you plan multiple incremental tranches, factor the cumulative cost into your financial model.
SDLT (Stamp Duty) Treatment
SDLT on shared ownership is more complicated than a standard purchase. You have two options at the point of first purchase:
Option 1 — Pay on full market value upfront (MSTT election) You elect to pay SDLT on the full market value of the property immediately, as if you'd bought the whole thing. This costs more now but means you pay no further SDLT on any future staircases.
Option 2 — Pay on your initial share only, defer the rest You pay SDLT only on the value of the share you're buying. When you staircase to 80% or above, you pay SDLT on the total share purchased to date. Below 80%, no further SDLT is due on subsequent staircases.
For first-time buyers taking advantage of first-time buyer SDLT relief (nil-rate up to £300,000 on shares, subject to qualifying conditions post-April 2025 threshold changes), the second option is often cheaper overall — but run the numbers for your property price.
What Changes When You Reach 100%?
Reaching full ownership is significant:
- Ground rent: Ceases entirely (you own the freehold interest or a long lease, depending on the property type).
- Subsidised rent: Stops — you no longer pay any rent to the housing association.
- Service charge: Continues — this covers building maintenance, communal areas, buildings insurance, and management. It doesn't disappear at 100%.
- Lease extension: You now have full leaseholder rights, including the right to extend your lease under the Leasehold Reform Act. See our lease extension guide for the process and costs.
When Does Staircasing Make Financial Sense?
Staircasing makes sense when:
- You have surplus equity or savings and the investment return from staircasing exceeds what that capital would earn elsewhere.
- Interest rates are lower than the net benefit of reducing your rent bill. Run the numbers: if staircasing saves you £200/month in rent but you're borrowing at 5.5%, the maths may be marginal.
- You want to sell and the buyer wants a larger share or full ownership.
- Your property has risen in value and you want to lock in at current prices before it rises further.
Staircasing is less compelling when interest rates are high, when your lease has significant ground rent issues that require resolving first, or when you have high-interest debt that should be paid down first.
Bottom Line
Staircasing is the route to full homeownership from shared ownership. Budget £1,000–£2,500 in costs per transaction, factor in RICS valuation timing (3-month window), and choose your SDLT approach at the point of first purchase. Full ownership eliminates rent and maximises your rights — but the journey there needs careful financial planning.
For a full picture of what shared ownership involves before you start staircasing, see our leasehold flat checklist and the conveyancing process timeline for how the legal steps work on each transaction.
For a guide to the shared ownership model, what replaced Help to Buy, and the full landscape for first-time buyers today, see our Help to Buy alternatives and shared ownership guide.
If you reach 100% ownership and your building has a third-party freeholder, collective enfranchisement under LRHUDA 1993 and LFRA 2024 lets leaseholders buy the freehold outright — eliminating the freeholder and giving you full control of building management. See our leasehold enfranchisement guide for the full process, premium calculation, and LFRA 2024 changes.