What the standard VAT/GST rate is
The standard VAT or GST rate is the rate applied to most goods and services that are not reduced-rated, zero-rated or exempt. OECD Consumption Tax Trends publishes each country's standard rate as at 1 January of the year, so the series reflects the law in force at the start of the calendar year. Reduced rates, zero rates and exemptions are not captured by this single number.
Some economies in the wider set are outside the OECD consumption-tax tables, and the United States has no federal VAT or GST at all. Where a rate is missing, the country page says so plainly rather than filling the gap.
Values are recorded as at 1 January each year, following the OECD's convention, so a rate change that takes effect during a year appears from the following 1 January onward; the series starts in 2005. Temporary measures — inflation-relief cuts, pandemic-era reductions and the like — are documented in the source's own tables and are deliberately not blended into the standard series here.
Because the standard rate is only one part of a consumption tax system, two countries with the same standard rate can collect very different amounts in practice: the reduced-rate schedules below it, the exemptions, and the registration thresholds all shape what is actually raised. Use this page for headline comparison, and the OECD Consumption Tax Trends tables for the detail.