Three names turn up in quotes for the same piece of work, and the difference between them is marketing rather than method. A WCAG audit names the standard, an ADA website audit names the law it is usually bought because of, and a digital accessibility audit names the scope when documents and apps are included alongside the site. What decides quality is the sample, the passes and the evidence, not the label on the invoice. On the worked example the same job is $3,480 with a $1,392 retest, whichever of the three names is on the quote.
What the three names actually differ on
Scope. A WCAG audit is scoped to pages measured against the criteria; an ADA website audit is the same work, usually with a short note about legal exposure that your lawyer rather than your auditor should be writing; a digital accessibility audit widens the scope to documents, mobile apps and sometimes kiosks. Ask which of your assets are in scope and the naming question answers itself.
What to compare between quotes
Sampled page count, the interaction types covered, the browser and screen reader pairs, whether 200% zoom and keyboard-only passes are included, whether findings carry criterion references, and whether a retest is priced. Two quotes at very different prices usually differ on sample size, and the sheet makes that comparable: 8% of 240 pages is 19 opened and 220 nobody sees.
What the report has to contain to be worth buying
Findings against criteria with reproduction steps, grouped by template rather than by page, with a remediation order and an estimate of effort. A report that lists 401 issues page by page with no grouping is a spreadsheet you will have to rewrite before your developers can start.
Questions people ask about digital accessibility audit
Is a WCAG audit enough for ADA?
In practice yes: the Department of Justice's own guidance points at WCAG as the measure, and no regulation sets a different technical standard for private websites.
Should the audit cover our web app?
If customers use it, yes, and expect it to cost more per page: an application's states are what take the time, not its URLs.
Can one supplier audit and remediate?
They can, and many do. Ask for the retest to be quoted separately so the check on the work is not bundled into the work.