An apostille is a certificate that verifies all of the following:

- that the signature of a public official (a notary public, for instance) on a document is genuine, for use abroad,

- the official capacity in which that person signed, and

- where relevant, the authenticity of any seal or stamp on the document, such as a notary seal.

Apostilles are generally issued by the Secretary of State (or equivalent office) of the state where the document was signed. Every country that joined the Hague Convention accepts them — and both Mexico and the US are signatories.

There are at least two routes to getting a document (a power of attorney, for example) apostilled.

1. The do-it-yourself route: have a notary public sign and seal the document, then mail it or bring it to your state's Secretary of State office (or equivalent). They confirm that the notary you used is licensed and legitimate, usually by attaching a verification page.

Going this route, the apostille typically runs $10-25 USD, plus a small notary fee of around $2-25 USD.

2. Depending on how far you live from your state's office, an apostille service may be faster, more convenient, and possibly even cheaper. These services often come to your home or meet you somewhere public to notarize the document, then submit it to the State Department for you. Expect fees starting around $300 USD.

Whichever route you choose, search online for "apostille" plus your state's name and several options will appear. If time is tight, call the State Department or the apostille service directly — we've seen official websites advertise 7-day turnarounds while the actual backlog, when you call, turns out to be three weeks.

Because Canada never signed the Hague Convention, Canadians (and citizens of other non-signatory countries) must instead have their POA authorized at a Mexican Embassy or Consulate.