How do you address wedding invitations without an inner envelope?

When you skip the inner envelope, the outer envelope does all the work. Write the names of every invited person on the front, in full, so there is no confusion about who is included. For a couple, write both names on one line, such as Mr James Smith and Ms Anna Jones. For a family, list parents and children by name if children are invited. If you are inviting a guest with a partner whose name you do not know, write the invited person's name followed by "and guest" on the same line. Avoid initials where possible, and use correct titles. If you are unsure of a title, it is fine to use the full name without one. The address goes in the bottom left or centre of the front, with the postcode on its own line. Make sure your handwriting is neat, or use printed labels. The outer envelope is what the postal service sees, so keep it clear and tidy. If you are worried about children or extra guests, write names exactly as you want them to attend. This is the kindest way to avoid awkward questions later.