How to Add Wax Seals to Wedding Invitations (Without Them Cracking in the Post)

Wax seals are the detail guests notice before they have read a word of the invitation. They are also the detail most likely to arrive in pieces, because traditional sealing wax was designed for hand-delivered letters, not automated sorting machines.

Here is how to do it properly, including the decision that matters most: whether to seal onto the envelope at all.

The decision that comes first: direct seal or adhesive seal

You have two options, and picking the wrong one is what causes most problems.

Sealing directly onto the envelope

Beautiful, traditional, and the seal is genuinely part of the envelope. It is also thicker, catches in sorting machinery, and often requires hand-cancelling at the post office and extra postage. Best for invitations you are hand-delivering or posting inside an outer envelope.

Ready-made adhesive seals

You make the seals in batches on a silicone mat, let them cure, then stick them on with the adhesive backing. You can make a hundred while watching television, none of them are attached to anything you can ruin, and any that come out badly go in the bin instead of costing you an envelope. This is what most people should do for a large guest list.

Our ready-made wedding invitation seals come with self-adhesive backs in sets of 25, 50 and 100.

Choosing wax that survives the post

This is where most wedding seals fail. Traditional shellac-based sealing wax is hard and brittle by design — it shatters rather than bends, which is exactly what you do not want inside a mail sorting machine.

Use a flexible wax blend, sometimes sold as postal wax or flexible sealing wax. It contains a plasticiser, so a seal will flex under pressure and spring back instead of cracking. It looks identical once set.

Glue-gun wax sticks are almost always flexible blends and are the fastest option for volume. Traditional wick sticks give a softer, more irregular edge that some people prefer aesthetically.

Step by step

1. Set up. Silicone mat, stamp, wax, melting spoon and candle or a low-temperature glue gun. Keep a small bowl of cold water nearby for the stamp.
2. Melt the wax. Two or three beads per seal in the spoon, held above the flame rather than in it. In the flame, wax scorches and browns.
3. Pour. One steady pour into a circle roughly 25mm across. Pour from low down — dropping wax from height traps bubbles.
4. Wait five seconds. The most skipped step. Stamping molten wax squeezes it out into a thin messy halo. Let it start to skin over.
5. Press straight down. Firm, even, no wiggling. Hold for five seconds.
6. Lift straight up. Any twist smears the impression.
7. Cool the stamp between seals. Touch it to a damp cloth. A hot stamp sticks; this is the reason seals tear as you lift.

How much wax do you actually need

Roughly three wax beads per seal, or one glue-gun stick per eight to ten seals. For a hundred invitations, buy enough for 120 — you will lose some to practice, and a few to a stamp that was still too hot.

Everything needed for a full invitation suite is bundled in our wax seal kits, sized by guest count.

Getting a clean impression every time

If your seals look muddy, it is almost never the wax. It is one of these:

• A shallow stamp. Budget stamps are engraved shallow and simply cannot produce definition. Depth is the single quality difference in a wax seal stamp.
• Stamping too soon. Five seconds. Count them.
• Too little wax. A thin pool spreads to nothing under pressure.
• A warm stamp. Cool it every single time.

Frequently asked questions

Will wax seals survive being posted?

Flexible wax will. Traditional shellac wax often will not. If you are sealing directly onto envelopes, use flexible wax and consider hand-cancelling at the post office.

Do wax seals cost extra postage?

Often yes, because the envelope becomes non-machinable. Take one finished invitation to the post office and have it weighed and measured before you buy stamps for the whole batch.

How far in advance can I make wax seals?

Months. Cured wax seals are stable — store them flat in a box, not stacked in a bag where the adhesive can pick up dust.

Can I use a glue gun for wax seals?

Yes, and for large batches it is the practical choice. Use a low-temperature gun and wax sticks made for sealing, not craft glue sticks.

What size wax seal is right for an invitation?

25mm is standard and suits most envelopes. 30mm makes a statement on larger suites; 20mm suits place cards and small tags.