Official sources first
Every closure is tied to a government, regulator, venue, central bank, or enacted rule.
Verified calendars · Source-level evidence
Dates you can
defend.
Most calendar tools hand you a date. ProvenDay shows the calendars, closures, official sources, and rule version that produced it.
6launch calendars
112verified events
13official sources
0guessed dates
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A narrower, stronger promise
We publish what the evidence supports.
Nothing more.
Rules stay versioned
A historical T+2 calculation does not silently use today’s T+1 convention.
Unknown means unknown
Outside confirmed coverage, the API returns a clear boundary error instead of an estimate.
Coverage ledger
Small enough to verify.
| Calendar | Type | Verified range | Status |
|---|---|---|---|
United States Federal HolidaysUS-FEDERAL | public | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |
England and Wales Bank HolidaysGB-EAW | public | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |
Scotland Bank HolidaysGB-SCT | public | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |
Northern Ireland Bank HolidaysGB-NIR | public | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |
New York Stock ExchangeXNYS | market | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |
Eurosystem T2 Euro SettlementTARGET | settlement | Thu, Jan 1, 2026 – Fri, Dec 31, 2027 | Confirmed |