Trust
Data Sources and Calculation Method
The calculator is designed around official tariff and HMRC guidance sources. Each estimate records tariff date, exchange-rate period and source status where available.
UK import rules checked: 13 October 2026 — £135 relief still applies to eligible GB imports
Current Great Britain rules: non-excise consignments with an intrinsic goods value of £135 or less normally have no customs duty; perfumes and toilet waters are excluded from this relief. VAT can still be due, usually at checkout or by business reverse charge for qualifying overseas sales.
HMRC plans to remove the £135 customs-duty relief by October 2028 at the latest. The commencement date will be set by regulations. These future rules are not applied to today's estimates. HMRC policy paper.
Vaping Products Duty started on 1 October 2026 at £2.20 per 10 ml, including nicotine-free vaping liquids. Excise goods need specialist calculations and are not supported here. HMRC vaping update.
Sources used
- GOV.UK Trade Tariff Public API V2
- GOV.UK Trade Tariff
- HMRC customs valuation guidance
- HMRC import VAT valuation guidance
- Postponed VAT accounting guidance
Cache and stale data
Tariff responses are cached for 24 hours. If a live refresh fails, the API can use the last successful cache where available and shows a stale-data warning. If no cache exists, a small labelled reference dataset can be used for the few codes it explicitly covers. Other failed lookups are marked unavailable and no duty estimate is produced.
“Live” describes a successful tariff lookup. “Cached” is within the refresh window, “stale” is the last successful snapshot after refresh failed, and “fallback” is limited built-in reference data. The time the result was generated is shown separately and does not make an older or fallback rate fresh.
Estimate only. Final liability depends on the accepted customs declaration, commodity classification, origin evidence and supporting documents. Not legal or tax advice. Not affiliated with HMRC or GOV.UK.