How long should a engagement message be?

Short and warm. Two or three delighted sentences that mention the pair rather than the wedding.

When should you send a engagement message?

Do not ask about the date. Everyone else is.

Engagement

An engagement is a private decision that has just become public, and the couple are about to be asked about logistics by everyone they meet.

A message that is about them rather than the wedding is a genuine relief.

Congratulate the decision, not the event. Nothing about venues, dates or plans.

Say something about the two of them or about the one you have known longest.

The best engagement messages sound delighted rather than impressed.

Who you are writing to changes the message more than the occasion does. Each page below is written for one relationship.

Do not ask about the date. Everyone else is.
For a long-term couple, the joke that it took them long enough is extremely common - skip it.
This is a good moment to say something you have thought for a while about how right they are together.

What should you write in a engagement message?: Congratulate the decision, not the event. Nothing about venues, dates or plans. Say something about the two of them or about the one you have known longest.
How long should a engagement message be?: Short and warm. Two or three delighted sentences that mention the pair rather than the wedding.
When should you send a engagement message?: Do not ask about the date. Everyone else is.

Say it as something they open

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