What is the proper etiquette for addressing wedding invitation envelopes?

The outer envelope is the formal one. Write the guest's full name with their title, such as Mr John Smith or Dr Jane Doe. For a married couple with the same surname, you can write Mr and Mrs John Smith, or list both first names, Mr John Smith and Mrs Jane Smith. For same-sex couples, use the same pattern with their preferred titles.

For the inner envelope, you can be less formal. Write just the titles and surnames, such as Mr Smith and Mrs Smith, or just first names if you are close. If children are invited, include their names on the inner envelope, either on the same line or below their parents.

Always use the guest's preferred title and name. If you do not know, use the standard form for their gender or use Mx. Avoid abbreviations like 'St.' for street, write it out fully. Use a clear, legible handwriting style or printed labels. Check every name and address twice before posting. If a guest has a professional title, like Dr or Reverend, use it on the outer envelope, it shows respect.