# UK Working Day Checker

> Checks whether a date is a normal working day in England and Wales, Scotland or Northern Ireland using a pinned snapshot of the official GOV.UK bank-holiday feed.

- Calculator id: `uk-working-day` · Category: Everyday Life (`everyday`) · Tool name: `check_uk_working_day`
- Canonical page: https://tttkmbb.com/everyday/uk-working-day · This document: https://tttkmbb.com/everyday/uk-working-day.md · JSON definition: https://tttkmbb.com/everyday/uk-working-day.json

## Purpose

Checks whether a date is a normal working day in England and Wales, Scotland or Northern Ireland using a pinned snapshot of the official GOV.UK bank-holiday feed.

**Use when:** You need to know whether a 2024-2028 UK date is a Monday-Friday working day after applying the official bank holidays for the selected division.

**Do not use when:** You need a local council, school, employer, financial-market, emergency-closure or non-UK calendar, or a date outside 2024-2028.

## Example user requests

- Is 28 December 2026 a working day in England and Wales, or the Boxing Day substitute holiday?
- Is Scotland working on 15 June 2026?
- Check whether 13 July 2026 is a working day in Northern Ireland.


## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `date` | date |  | required | UK civil date in YYYY-MM-DD format, within 2024-2028. |
| `division` | enum: england-and-wales \| scotland \| northern-ireland |  | optional, default "england-and-wales" | GOV.UK bank-holiday division. England and Wales share one official list; Scotland and Northern Ireland have separate lists. |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `date` | date |  | Checked civil date. |
| `weekday` | string |  | Gregorian weekday. |
| `division` | string |  | Canonical GOV.UK division id. |
| `division_name` | string |  | Human-readable UK division. |
| `is_working_day` | boolean |  | True only for Monday-Friday dates not listed as a bank holiday. |
| `day_type` | string |  | bank_holiday, regular_weekend or regular_weekday. |
| `bank_holiday_name` | string |  | Official event title when the date is a bank holiday; otherwise empty. |
| `bank_holiday_notes` | string |  | GOV.UK notes such as Substitute day; otherwise empty. |
| `status_basis` | string |  | Evidence-based explanation for the classification. |
| `source_url` | string |  | Official GOV.UK JSON source. |
| `licence` | string |  | Reuse licence for GOV.UK content. |
| `dataset_version` | string |  | Pinned Calcgrid snapshot version of the GOV.UK bank-holiday package. |
| `coverage_start` | date |  | First supported date in this pinned package. |
| `coverage_end` | date |  | Last supported date in this pinned package. |
| `source_snapshot_sha256` | string |  | SHA-256 of the complete official GOV.UK JSON response used for this package. |

## Formula

`official bank-holiday event → non-working; else Saturday/Sunday → non-working; else Monday-Friday → working`

The selected division's official GOV.UK bank-holiday events are applied before the ordinary Monday-Friday rule. Substitute-day notes are preserved, and every result returns the pinned dataset version and source hash.

## Data Sources

- GOV.UK Bank Holidays API — https://www.gov.uk/bank-holidays.json (government, retrieved 2026-09-26)
- Open Government Licence v3.0 — https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ (licence, retrieved 2026-09-26)

Data freshness: `static`. Pinned official GOV.UK snapshot retrieved 2026-09-26; coverage 2024-2028. The upstream feed is checked before a new snapshot is published.

## API

- `GET https://tttkmbb.com/api/v1/calculate/uk-working-day?date=…`
- `POST https://tttkmbb.com/api/v1/calculate/uk-working-day` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/uk-working-day · OpenAPI operationId `check_uk_working_day` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool: `check_uk_working_day` (dedicated) or `run_calculator` with `{"calculator_id": "uk-working-day", "inputs": {…}}`

## Example

- England and Wales Boxing Day substitute: inputs `{"date":"2026-12-28","division":"england-and-wales"}` → `{"weekday":"Monday","is_working_day":false,"day_type":"bank_holiday","bank_holiday_name":"Boxing Day","bank_holiday_notes":"Substitute day"}`
- Scotland World Cup bank holiday: inputs `{"date":"2026-06-15","division":"scotland"}` → `{"weekday":"Monday","is_working_day":false,"day_type":"bank_holiday","bank_holiday_name":"World Cup bank holiday"}`

```
GET https://tttkmbb.com/api/v1/calculate/uk-working-day?date=2026-12-28&division=england-and-wales
```

## Limitations

You need a local council, school, employer, financial-market, emergency-closure or non-UK calendar, or a date outside 2024-2028. The selected division's official GOV.UK bank-holiday events are applied before the ordinary Monday-Friday rule. Substitute-day notes are preserved, and every result returns the pinned dataset version and source hash. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**Why are there three UK divisions?**

GOV.UK publishes separate bank-holiday lists for England and Wales, Scotland and Northern Ireland. Choosing the wrong division can change the answer.

**Does this include local or employer holidays?**

No. It applies the official national/division bank-holiday feed and the ordinary weekend rule only.

## Related

- [Add UK Working Days](https://tttkmbb.com/everyday/uk-add-working-days.md) — Add or subtract UK working days.
- [UK Working Days Between Dates](https://tttkmbb.com/everyday/uk-working-days-between.md) — Count UK working days in a range.
- [Mainland China Working Day Checker](https://tttkmbb.com/everyday/china-working-day.md) — Check the mainland China official calendar including 调休.