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Property · Mortgage + rent

Shared Ownership Calculator

Shared Ownership lets you buy 10–75% of a home with a mortgage, and pay subsidised rent to a housing association on the rest. Smaller deposit, but two monthly costs.

£
%
%
yrs
%

Total monthly housing cost

£1,114

Mortgage on £120,000£702
Rent on £180,000£413
Total£1114

How we calculated your result

Mortgage is calculated on your share using standard amortisation. Rent is typically 2.75% of the unowned share value per year (set by the housing association — check your scheme). Total = mortgage + rent.

Official UK rules in simple English

  • Minimum share usually 10–25%; max 75%.
  • Rent capped at 3% of unowned share, but most schemes use 2.75%.
  • You can ‘staircase’ — buy more shares over time, reducing rent.
  • Stamp Duty: pay on the share you buy, or on the full value (one-off).

Common pitfalls to watch out for

  • ⚠ Service charges on top

    Most SO is leasehold flats with ground rent + service charge. Add £100–300/month.

  • ⚠ Selling is harder

    Housing association has first refusal & nominate buyers — can take months.

  • ⚠ 100% staircased? Still leasehold

    Unless freehold from day one, you’ll deal with the lease forever.

Frequently asked questions

What deposit do I need?
Usually 5–10% of the share, not the full property — making SO accessible at lower deposits.
Rent goes up?
Yes — usually RPI + 0.5% annually, fixed in your lease.

Illustrative. Always check the specific scheme’s rent formula, service charge and staircasing terms.

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