What leasehold data is available via API in the UK?

Via the Homedata API and HMLR title data, you can access: tenure type (leasehold/freehold/commonhold), title number, registered proprietor, and date of registration. Full lease length and ground rent figures are contained within the lease document itself (filed at HMLR) rather than in structured digital fields — these require a title register and associated documents purchase from HMLR at £3–£7 each.

Leasehold Property Data API: Ground Rent, Tenure & Reform 2026

Q: What does the Commonhold and Leasehold Reform Bill 2026 change?

The Commonhold and Leasehold Reform Bill, published in January 2026, proposes to cap ground rents at £250 per year for existing leases and prohibit new ground rent clauses in new leases. It also seeks to make commonhold — where residents own the freehold of a block collectively — the default tenure for new flats. The Bill is currently passing through Parliament and is expected to receive Royal Assent in late 2026.

Q: How do I find out if a property is leasehold?

The tenure of a registered property in England and Wales is visible in the HM Land Registry title register. The Homedata API returns tenure (leasehold, freehold, or commonhold) for any UPRN as part of the ownership endpoint response, without requiring a manual HMLR search.

Q: How many leasehold properties are there in England?

There are approximately 5 million leasehold dwellings in England — around 20% of the housing stock. The majority are flats, but around 1 million are leasehold houses, a tenure type that the Leasehold Reform (Ground Rent) Act 2022 and the forthcoming Commonhold and Leasehold Reform Bill are specifically targeting.

The leasehold tenure problem

England and Wales have approximately 5 million leasehold dwellings — mostly flats but including around 1 million leasehold houses. Leaseholders own the right to occupy a property for a fixed term (often 99 or 125 years, sometimes 999) and pay ground rent to the freeholder. As leases shorten below 80 years they become progressively harder to mortgage, and lease extension costs escalate significantly below 70 years.

For conveyancers, mortgage lenders, and valuation surveyors, understanding a property's tenure and remaining lease length is essential. The challenge: this data is not fully structured in any government open dataset.

What leasehold data is digitally accessible

HM Land Registry's digital title register — accessible at £3 per title — contains:

Tenure type (leasehold / freehold / commonhold)
Title number
Registered proprietor
Date of latest registration
Price paid on last sale (where applicable)

The lease length and ground rent figure are contained within the lease document filed at HMLR, not in the structured digital register. Accessing them requires downloading the associated lease document (£3–£7 per document), which is a PDF. Automated extraction requires OCR or structured document parsing.

Accessing tenure data via the Homedata API

The Homedata ownership endpoint returns tenure type for any UPRN in England and Wales — freehold, leasehold, or commonhold — as structured JSON, without requiring a manual HMLR search.

GET /api/properties/10023456789/ownership/
Authorization: Api-Key YOUR_KEY

{
  "uprn": "10023456789",
  "title_number": "AV98765",
  "tenure": "leasehold",
  "proprietor": "Patel, Ananya",
  "registered_date": "2021-07-08",
  "title_class": "good_leasehold"
}

The Commonhold and Leasehold Reform Bill 2026

Published in January 2026, the Bill is the most significant reform to leasehold law since the Leasehold Reform, Housing and Urban Development Act 1993. Key provisions:

Ground rent cap — existing ground rents capped at £250/year; new leases prohibited from charging any ground rent.
Commonhold default — new residential flat developments to use commonhold tenure where residents collectively own the freehold.
Statutory lease extension — leaseholders can extend by 990 years at zero ground rent (for flats) or 990 years (for houses).
Right to manage — threshold for qualifying tenants reduced from 50% to 25%.

For data providers, the reform will increase demand for tenure screening tools — particularly portfolio-level checks to identify high ground rent leases (above £250/year) that may trigger the cap.

Use cases for leasehold data access

Conveyancers — flag leasehold tenure at instruction; identify titles requiring lease extension advice.
Mortgage lenders — screen applications for short leases (below 70 years) that breach lending criteria.
Portfolio managers — identify leasehold properties in a portfolio ahead of the ground rent cap deadline.
Proptech developers — surface tenure information on property search and comparison tools.

Frequently asked questions

What leasehold data is available via API?

Tenure type (leasehold/freehold/commonhold), title number, and registered proprietor via the Homedata ownership endpoint. Full lease length and ground rent require a title document purchase from HMLR.

What does the Commonhold and Leasehold Reform Bill 2026 change?

Ground rents capped at £250/year for existing leases; banned for new leases. Commonhold set as the default tenure for new flat developments.

How do I find out if a property is leasehold?

The Homedata ownership API returns tenure for any UPRN as structured JSON. Alternatively, search HMLR's digital portal for £3 per title.

How many leasehold properties are there in England?

Approximately 5 million — around 20% of the housing stock, predominantly flats.