The data behind KnowYourSponsor

Everything this site shows is published as plain JSON, rebuilt every day from the official GOV.UK register. It is free to use, needs no account, and you are welcome to build on it.

Start here

If you only want one thing, it is regional_changes.json: the employers that gained or lost a licence in the last seven days, split by town. That is the part the official register does not publish, because it shows only who holds a licence today and never who stopped.

There is also an RSS feed if you would rather not write any code at all.

The files

data/sponsors.json

Every licensed sponsor on the register.

{"updated": "...", "source": "...", "sponsors": [[name, town, county, industry, [routes], rating], ...]}

About 10MB uncompressed, served gzipped. Rows are arrays, not objects, to keep it small.

data/company_flags.json

Employers whose company record raises a question at Companies House.

{"updated": "...", "snapshot": "YYYY-MM-01", "stats": {...}, "companies": {"Employer Name": {"number": "...", "status": "...", "flags": ["not_active", ...]}}}

Keyed by the employer's name exactly as the register spells it. Matched by name, so treat it as a pointer to the Companies House record rather than proof.

data/regional_changes.json

The same changes, split by town or city.

{"updated": "...", "window_days": 7, "totals": {...}, "regions": {"London": {"added": [...], "removed": [...], "slug": "london"}, ...}}

Built for exactly one job: sending someone the changes in their own area.

data/new_sponsors.json

Employers licensed in the last 7 days.

{"updated": "...", "window_days": 7, "new": [row, ...]}

data/removed_sponsors.json

Employers removed in the last 7 days.

{"updated": "...", "window_days": 7, "removed": [row, ...]}

data/meta.json

Counts and the last update time. Small, cheap to poll.

{"updated": "...", "total": 0, "added_recently": 0, "removed_recently": 0, "window_days": 7}

Poll this first and only fetch the big files when "updated" has moved.

feed.xml

RSS feed, one item per day that changed.

RSS 2.0

For readers, and for anything that turns a feed into email.

feeds/<city-or-industry>.xml

The same changes, filtered to one city or one industry.

RSS 2.0, one item per employer

One per landing page, so feeds/london.xml and feeds/healthcare-care.xml both exist. Each item has a permanent guid, so polling it will not re-notify you about the same employer twice. This is the free version of a filtered feed; email delivery and watchlists are the paid one.

How to use it kindly

The pipeline runs once a day, at 05:30 UTC. Polling more often than hourly only costs you bandwidth.
Check meta.json first. It is small, and its updated value tells you whether anything moved.
These are static files on GitHub Pages. There is no authentication, no rate limit, and no uptime guarantee. Do not put anything critical behind them without caching your own copy.
A row is an array, in this order: name, town, county, industry, routes, rating. Industry is our own guess from the employer's name, not official data.

Licence and credit

The underlying register is Crown copyright, published under the Open Government Licence v3.0. The cleaning, the industry tags and the change history are ours, and you may use them freely. A link back is appreciated but not required.

The register covers 127,701 employers.

What is not here

These files cover the current register and the last seven days. We keep a dated snapshot of the register every single day, which means we can answer questions the files above cannot: when an employer first appeared, how long it held a licence, which sectors are growing, what changed in any given month.

That history only exists because it has been collected day by day. GOV.UK publishes today's register and never what left it, so it cannot be reconstructed after the fact by anyone, including us.

Need the history, or a cut of your own?

If you need a longer history, a filtered feed for one region or sector, or a regular export for your team, email me and tell me what you are trying to do. It is easier to build the thing somebody actually asked for than to guess at it.

Useful things to say: which sectors or regions you care about, how far back you need, and how you would rather receive it. I reply to everything.

Email hello@knowyoursponsor.co.uk Or see what it costs