# Add Belgium Working Days

> Adds or subtracts Belgium authority-scope working days in exact coverage.

- Calculator id: `belgium-public-add-working-days` · Category: Everyday Life (`everyday`) · Tool name: `add_be_working_days`
- Canonical page: https://tttkmbb.com/everyday/belgium-public-add-working-days · This document: https://tttkmbb.com/everyday/belgium-public-add-working-days.md · JSON definition: https://tttkmbb.com/everyday/belgium-public-add-working-days.json

## Purpose

Adds or subtracts Belgium authority-scope working days in exact coverage.

**Use when:** You need a deterministic Belgium working-day offset.

**Do not use when:** Private-sector statutory core only; substitute dates, public-service/community/regional holidays, sector agreements, employer, school, bank and municipal schedules are not inferred.

## Example user requests

- Add or subtract Belgium working days around Belgian National Day.
- Add or subtract Belgium working days around Ordinary weekday.


## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `start_date` | date |  | required | Gregorian start date in 2026-2027. |
| `working_days` | integer |  | required | Signed offset; start date excluded for non-zero offsets. (min -1000, max 1000) |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `start_date` | date |  | Input date. |
| `result_date` | date |  | Date reached. |
| `working_days_added` | integer |  | Signed requested offset. |
| `calendar_days_elapsed` | integer |  | Signed Gregorian difference. |
| `public_holidays_skipped` | list |  | Exact events crossed. |
| `territory` | string |  | BE (Belgium). |
| `territory_name` | string |  | Belgium |
| `day_type` | string |  | Deterministic classification: official_weekend, regular_workday, or the first published authority event kind. |
| `holiday_names` | string_list |  | Events applying on the date. |
| `holiday_kinds` | string_list |  | Authority event classifications. |
| `holiday_details` | list |  | Structured event details, including partial-day notes where published. |
| `calendar_scope` | string |  | Belgium ten statutory private-sector public holidays for 2026-2027 |
| `holiday_policy` | string |  | The ten statutory Belgian labour public holidays are included; the public-sector, community, regional, sector and employer calendars are not substituted into this national core. |
| `substitute_day_policy` | string |  | No substitute-day closure is inferred. If a statutory holiday coincides with Sunday or an undertaking's ordinary inactivity day, the substitute day is fixed by the competent joint committee or undertaking. |
| `calendar_profile` | string |  | belgium-public-holidays |
| `dataset_version` | string |  | be-legal-public-holidays-2026-2027.1 |
| `sources` | list |  | Authority and legislation sources. |

## Formula

`move one day at a time; decrement only on status.is_working_day=true`

Skip Saturday/Sunday and exact pinned authority events; do not add unverified substitute days.

## Data Sources

- Belgian Federal Public Service Employment – Public holidays — https://employment.belgium.be/en/themes/international/posting/working-conditions-be-respected-case-posting-belgium/public-holidays (government_labour_guidance)
- Belgium.be – legal holidays — https://www.belgium.be/nl/werk/verlof_en_loopbaanonderbrekingen/feestdagen (government_calendar_reference)
- Belgian Federal Public Service Employment – public-holiday regulation — https://employment.belgium.be/en/regulation-public-holidays (government_regulation_index)

Data freshness: `static`. Pinned be-legal-public-holidays-2026-2027.1 package.

## API

- `GET https://tttkmbb.com/api/v1/calculate/belgium-public-add-working-days?start_date=…&working_days=…`
- `POST https://tttkmbb.com/api/v1/calculate/belgium-public-add-working-days` 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/belgium-public-add-working-days · OpenAPI operationId `add_be_working_days` 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:  `run_calculator` with `{"calculator_id": "belgium-public-add-working-days", "inputs": {…}}`

## Example

- Zero offset is identity: inputs `{"start_date":"2026-01-01","working_days":0}` → `{"result_date":"2026-01-01","working_days_added":0}`

```
GET https://tttkmbb.com/api/v1/calculate/belgium-public-add-working-days?start_date=2026-01-01&working_days=0
```

## Limitations

Private-sector statutory core only; substitute dates, public-service/community/regional holidays, sector agreements, employer, school, bank and municipal schedules are not inferred. Skip Saturday/Sunday and exact pinned authority events; do not add unverified substitute days. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**Are substitute days included?**

No. Belgium fixes a replacement rest day through the competent joint committee or undertaking when a statutory holiday overlaps an ordinary inactivity day; this package preserves the statutory date and does not infer the replacement.

## Related

- [Belgium Working Day](https://tttkmbb.com/everyday/belgium-public-working-day.md) — Inspect a date and source evidence.