Methodology
Every number on this site can be traced to a published source, and this page explains how we get from that source to the figure you read. Baby costs are unusually easy to get wrong: the widely quoted totals mix years, mix countries, mix households and are then repeated without their assumptions. Our rule is that a figure is only worth publishing if we can say who measured it, when, for whom, and what it excludes. Where we cannot, we say the number is an estimate and give the range instead of a false precision.
Which sources we use
- Official statistics first. The US Department of Agriculture expenditure study for the cost of raising a child, the Bureau of Labor Statistics Consumer Expenditure Survey for household spending, the Office for National Statistics for UK prices and earnings.
- Government schedules for anything a rule sets. Tax credits from the IRS, UK entitlements from GOV.UK, childcare programmes from childcare.gov, leave rights from the Department of Labor. These are copied, not estimated.
- Sector surveys where no public body measures the market, such as nursery and nanny rates, and only where the sample and the date are disclosed.
- Published prices for consumables like formula and nappies, collected from national retailers and stated as a range across brands.
Why we publish ranges
An average hides the thing that matters most. Infant childcare in the United States runs from roughly $6,000 a year in parts of the South to over $26,000 in Massachusetts and the District of Columbia; the national mean describes almost nobody. So costs appear here as a low-to-high range with the driver of the spread named next to it, and the calculators let you replace the range with your own figure. Where a single number is unavoidable, we say which household it describes.
Years, inflation and currencies
Each figure carries the year of its source. Older statistics are adjusted to current prices with the relevant national consumer price index, and we say when we have done so rather than presenting a restated figure as a fresh measurement. Cross-country comparisons are shown in local currency first, with an indicative conversion at the rate of the month of publication; exchange rates move, and a converted total is an illustration, not a quote.
What we exclude
Totals described as birth-to-eighteen stop at eighteen and exclude higher education, which is a separate and largely optional cost. Housing is included only as the marginal cost attributable to the child, not as the whole rent or mortgage. Lost earnings from a career break are treated separately in the going-back-to-work guide, because counting them inside a spending total double-counts the same decision.
Updating and corrections
Pages carry the date of their last review. Anything driven by an official schedule, tax credits, statutory pay, benefit caps, is checked when the schedule changes; market prices are reviewed annually. If you find a figure that is wrong or out of date, write to contact@bumpweek.com with the page and the number. Corrections are made on the page itself and the review date is moved, rather than quietly edited.
Independence
No brand, nursery chain, insurer or retailer pays for placement on this site, and no figure or recommendation is influenced by a commercial relationship. Where a product is named, it is named because its price is a data point.