Calculate the total monthly cost of a shared ownership home, including mortgage, rent on the remaining share, and service charges.
This calculator provides estimates only. It does not constitute financial advice. Shared ownership terms, rent levels, and service charges vary by housing association. Always obtain a full illustration from your housing provider and consult a qualified mortgage adviser.
Shared ownership is a government-backed scheme designed to help people who cannot afford to buy a home outright on the open market. Under the scheme, you buy a share of a property (typically between 25% and 75%) and pay rent on the remaining share to a housing association. This makes homeownership accessible with a smaller deposit and lower mortgage requirement. This calculator helps you understand the true monthly cost of a shared ownership property by combining the mortgage payment on your share, the rent on the housing association's share, and the monthly service charge. It also shows the deposit you will need and the total cost over the full mortgage term, giving you a complete picture of the financial commitment involved.
To calculate shared ownership costs: 1. Enter the full property value. This is the market value of the entire property, not just your share. 2. Use the slider to set your ownership share. Shared ownership schemes typically allow you to buy between 25% and 75% of the property. 3. Enter the mortgage interest rate. This is the rate you have been offered or expect to get on a shared ownership mortgage. Some lenders specialise in shared ownership products. 4. Set your mortgage term. 25 years is standard, but terms of 30 or 35 years are available and reduce monthly payments. 5. Adjust the advanced options if needed. The annual rent rate on the remaining share is typically 2.75% of the housing association's share value. Service charges cover maintenance of communal areas and building insurance. 6. Review the results. The total monthly cost combines your mortgage, rent, and service charge. The pie chart shows how your monthly payment breaks down between these three components. The deposit needed is calculated as 10% of your share.
The calculator works in several steps: Mortgage amount = full property value multiplied by your ownership share percentage. Deposit needed = 10% of the mortgage amount (i.e., 10% of your share, not the full property value). Loan amount = mortgage amount minus deposit. Monthly mortgage payment is calculated using the standard annuity formula: M = L x [r(1+r)^n] / [(1+r)^n - 1], where L is the loan amount, r is the monthly interest rate, and n is the total number of monthly payments. Monthly rent = full property value multiplied by the housing association's share (100% minus your share) multiplied by the annual rent rate, divided by 12. Total monthly cost = monthly mortgage + monthly rent + monthly service charge. Total cost over term = total monthly cost multiplied by the total number of months in the mortgage term. For example, a GBP 300,000 property with 40% ownership at 4% interest over 25 years: your share is GBP 120,000, deposit is GBP 12,000, and loan is GBP 108,000. Monthly rent on the remaining 60% at 2.75% is approximately GBP 412 per month.
The shared ownership scheme was reformed in 2021, introducing a 10-year repair and maintenance period during which the housing association is responsible for certain repairs. Initial staircasing shares of 10% are also available, making it easier to increase your ownership over time. Rent on the housing association's share is typically reviewed annually and may increase by RPI plus 0.5% or CPI plus 1%, depending on your lease terms. Service charges can also increase and are set by the housing association or management company. When you staircase (buy additional shares), the additional share is valued at the current market rate, which may be higher or lower than when you originally purchased. Once you own 100% of the property, you no longer pay rent to the housing association. Stamp duty on shared ownership can be paid either on the full property value upfront or on each staircasing transaction. Shared ownership properties may have restrictions on subletting and alterations. Always read your lease carefully and consider taking independent legal advice before purchasing.