208 UK Local Education Authorities. Every holiday, half term, and INSET day. 28 years of history. Weighted by pupil population. Available via API from £299/year.
Planning teams know school holidays matter, but have no reliable structured data to act on. They resort to guesswork, last year's rough notes, or manual research that never scales.
UK school calendars are set independently by each LEA. Half term in Birmingham can fall a week earlier than Manchester. We've structured all 208.
Without structured tracking, revenue teams only discover timing changes after the fact. Our 28-year history has the record — and the shifts are already in it.
Even teams with calendar data struggle to convert it into demand signals. Semestern delivers schema-consistent records you can pipe directly into models.
Semestern collects school calendars directly from each of the 208 UK Local Education Authority websites, cross-references them with pupil population data, and produces a clean consistent dataset updated each May.
Every product is derived from the same dataset — school holidays and pupil population by LEA and year group, covering 28 years.
Query holidays, half terms, INSET days, and term dates by LEA, nation, year, event type, or date range via a clean REST API.
Download complete structured datasets per nation or all 208 LEAs. Consistent schema across every academic year from 1996–97 onwards.
Each May, after the annual collection pipeline runs, Semestern compares the new academic year's dates against the previous year for every LEA and every event type. Where a date has moved, an alert fires — before commercial teams have committed to pricing and planning decisions for the coming year.
LEA-level school holiday data back to 1996–97, structured to the same schema as annual data. Built for backtesting demand models.
A forward annual calendar ranking the highest-impact UK break periods by pupil count, with LEA-level overlap and timing shift flags.
Total and year-group breakdown (Reception–Year 13) per LEA per year. Same 28-year series as the holiday data.
Pre-calculated pupils-off counts for any date, date range, or catchment. /impact/range returns a day-by-day time series ready for forecasting models. /compare checks up to 50 locations in one call. No analysis required.
Pass up to 50 LEA codes and a date. Receive school status and pupil count for every location at once — no looping, no batching. Built for national retailers, hotel groups, and multi-site operators checking their whole estate against a target date.
Holiday periods ranked by demand impact. Regional divergence windows. Year-by-year event history per LEA with consistency summaries. The endpoints that turn historical data into commercial intelligence.
The Semestern API delivers at two levels. Query the structured calendar data directly if you have analysts who build models and pipelines. Or call a pre-calculated endpoint and receive the answer — no analysis required. The same dataset. Two ways in.
Raw data endpoints are available on all tiers. Impact endpoints require Professional tier. Analytics endpoints are unlocked by purchasing either historical archive.
Plan promotions around the holidays that actually affect your stores, not the national average.
Forecast footfall by the pupil population in your catchment area, weighted to your specific geography.
Pinpoint exactly when the school-age population in each region is free to travel, by LEA origin.
Build smarter leave and scheduling models using granular term data and INSET day alerts.
A 28-year signal for consumer behaviour and transaction volume models at regional granularity.
28 years of consistent data. Train models. Backtest strategies. Find patterns at LEA level.
The dataset covers all 208 Local Education Authorities across all four nations — providing LEA-level precision where national calendar feeds miss the variation entirely.
Select the nations, LEAs, and years your team needs. Filter by year group if your use case is age-specific.
Query the REST API in real time or download structured CSV, JSON, or Parquet exports for offline analysis and model training.
Connect to your data warehouse, BI tool, or forecasting model. Historical and forward data in a consistent schema.
Subscribe annually for current data and API access. Add a historical archive once and pay 20% less every year. All prices exclude VAT.
Purchase a historical archive (from £2,500 one-off) and receive a permanent 20% discount on your subscription — every renewal year.
Request access and we will send sample data for your region within one business day.
Request AccessReach out to discuss which plan fits your use case. All contracts are invoiced — no card required, no automatic billing.
Tell us your use case and the regions you care about. We'll respond with a tailored proposal within one business day.
info@semestern.com →Prefer to talk through the data directly? We're happy to walk you through a live demo of the API and export options.
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