A wax seal is the impression left when an engraved die, called a matrix, is pressed into softened wax or a similar material. For centuries it did the job of a signature: it showed who had sent a document and that nobody had opened it on the way. Today it is mostly a finishing touch on invitations, letters and gift packaging, though a few formal uses survive.
This guide explains what a wax seal is, what it is made of, how the parts are named, where the tradition came from and what to do if you want a similar mark for your own stationery.
TL;DR
- A wax seal is the impression; the metal or wood die that makes it is the matrix. The two words are often mixed up.
- Seals began as proof of identity and authenticity. In England the practice goes back to at least the 11th century.
- Modern “sealing wax” sticks are usually shellac-based rather than pure beeswax, which is why they stay firmer and shinier.
- Wax seals are now mainly decorative, but wax, metal or plastic seals are still required on diplomatic bags.
- If you need a repeatable mark for business post, a self-inking stamp is the practical alternative to wax.
Table of Contents
- What a wax seal is, in plain terms
- Where wax seals came from
- What sealing wax is made of
- Applied seals and pendant seals
- Are wax seals still used?
- How a wax seal is made
- Posting a wax-sealed envelope
- Wax seal or rubber stamp: which do you need?
- Our perspective
- Getting a seal-style mark of your own
- Common misunderstandings
- Frequently asked questions
- Sources
What a wax seal is, in plain terms
The National Archives describe the term “seal” as usually applying to the impression left by an engraved metal die, the matrix, pressed into a material such as wax. Confusingly, the same word is also used for the matrix itself. Archivists prefer to keep them apart:
- Matrix: the engraved metal or wood die. It is the tool, and it often carries a coat of arms, initials or a personal emblem.
- Seal: the finished impression in wax. It is the result.
- Sealing wax: the material that takes the impression.
The University of Nottingham’s guide to medieval document authentication puts it simply: the pattern on the matrix is transferred to the warm wax. That is all a wax seal is. Everything else, the colours, the ribbons, the ceremony, is built on that one action.
What people call the parts
Searchers often ask “what is the wax seal called?” The honest answer is that it depends on which part you mean. The impression is the seal. The tool is the matrix, which most shops call a wax seal stamp. We cover that naming question further in our article on what a wax stamp is called.
Where wax seals came from
Seals are far older than wax. According to the Essex Record Office, wax seals were first used in the Middle Ages, although the Romans used a similar method with bitumen and the ancient Mesopotamians pressed seal marks into clay tablets.
In England, the National Archives trace the use of seal matrices in wax to at least the 11th century, with the seal of Edward the Confessor (c. 1042 to 1066) as an early example. Surrey County Council’s history centre explains the purpose: a seal was used to authenticate or validate a document in place of, or alongside, a signature.
That explains why seals mattered. In a world where many people could not write, a distinctive design pressed into wax was a recognisable mark of identity, and an unbroken seal showed a letter had not been read.
Who actually pressed the seal?
It is tempting to picture a lord stamping each document himself. Research suggests otherwise. Historians studying palm prints on medieval wax seals at Aberystwyth University note that the backs of seals can preserve fingerprints and palm marks, which show how the sealing was done. It was a physical, hands-on process, and administrative staff often carried it out rather than the owner.
What sealing wax is made of
Many people assume sealing wax is simply beeswax. Medieval wax largely was. The University of Lincoln’s First Impressions project notes that the principal ingredient of medieval sealing wax is beeswax, whereas the hard, shiny sticks sold today as sealing wax are shellac-based, shellac being produced by a beetle native to South East Asia.
This matters for anyone using wax in practice. The Surrey conservation guidance describes how traditional beeswax is naturally fragile: it loses moisture over time and becomes brittle, and conservators often strengthen seals with mixtures of wax and resin. Modern flexible sealing wax blends follow the same logic.
If you want the recipe side in more detail, including traditional formulations, read our guide to what sealing wax is made of.
Applied seals and pendant seals
There are two ways a seal can be attached, and the difference is useful when you see old documents or copy the style.
| Type | How it is attached | Typical use |
|---|---|---|
| Applied seal | Pressed directly onto the face of the document | Modern letters, invitations, packaging |
| Pendant seal | Hangs from the document on a tag, cord or ribbon | Medieval charters and formal grants |
The Surrey history centre records that pendant seals were preferred for official charters because wax could detach from the parchment surface. Ecclesiastical seals were often pointed-oval (vesica) shapes used in pendant form, sometimes with a different impression on each side, known as a counterseal.
For everyday use, applied seals are standard. The National Archives’ handling guidance lists wax, shellac and lead as the most common seal materials and confirms the applied and attached methods.
Are wax seals still used?
Yes, in two quite different ways.
Decorative use
The National Archives note that the wax seal is now primarily used for decoration on high-status stationery. You will see it on wedding invitations, thank-you notes, gift wrap, certificates and the flap of a handwritten letter. A custom stamp with initials, a monogram or a small emblem is the usual choice.
Formal and diplomatic use
A real functional requirement still exists. HMRC’s guidance on diplomatic bags says the package must bear a seal in wax, metal or plastic affixed by the competent authority of the sending state or mission. This follows Article 27.3 of the Vienna Convention on Diplomatic Relations. Outside that setting, wax seals no longer carry legal weight in the UK for ordinary correspondence.
How a wax seal is made
The process is simple, but a few details separate a crisp impression from a smudge.
- Prepare the surface. Use a firm paper or envelope flap. Keep your matrix clean and dry.
- Melt the wax. Use a sealing wax stick with a spoon or a melting device, or a glue-gun style wax rod. Pour or drip a pool slightly larger than the matrix.
- Let it cool a moment. A common mistake is stamping straight into very hot wax. The National Archives’ guidance on seals and wider practice suggest a clean impression comes when the wax has cooled slightly and is a little tacky. Hot wax tends to cling to the matrix and trap bubbles.
- Press and hold. Press the matrix down firmly and evenly for several seconds.
- Lift straight up. If wax sticks, a very light film of oil or moisture on the matrix can help next time.
Expect to ruin a few attempts. Practising on scrap card first costs nothing.
Posting a wax-sealed envelope
This is where the romance meets the sorting machine. The research we reviewed indicates that brittle wax can crack or shatter in automated mail machinery, and that bulky applied seals can sometimes cause problems with high-speed envelope handling. Practical points:
- Choose a flexible sealing wax blend rather than a brittle one if the envelope will travel.
- Keep the seal small and flat. Big, heavy seals are more likely to be damaged.
- For important items, consider a padded envelope or a protective outer layer.
- Check current postal guidance before sending valuable post.
Users on the Postcrossing community report that domestic wax-sealed cards mostly arrive intact, though those are individual experiences, not a guarantee.
Wax seal or rubber stamp: which do you need?
A wax seal is a gesture. A rubber stamp is a tool. They overlap in one respect: both let you apply a repeatable personal mark. The differences decide which is right for you.
| Question | Wax seal | Self-inking rubber stamp |
|---|---|---|
| Speed | Slow: melt, pour, wait, press | Instant: one press |
| Cost per use | Wax consumed each time | Ink lasts for many impressions; pads can be replaced |
| Postal handling | Can crack or snag in machines | Flat ink impression, no bulk |
| Look | Raised, tactile, decorative | Flat, clear, practical |
| Best for | Invitations, gifts, special letters | Business post, packaging, paperwork, admin |
If you run a small business and wanted a wax seal for branding, there is a good chance a stamp serves you better day to day. Our article on three rubber stamp types small businesses should consider instead of a wax seal goes through the options.
Our perspective
We make custom rubber stamps, so we see why people reach for a wax seal and why they often stop using one. The appeal is real: a wax seal looks personal and unhurried. The problem is that most of the people who contact us need something quick, clean and repeatable, whether that is a return address on 200 envelopes, a logo on packaging or an “Office Copy” mark on invoices.
Our advice is to separate the occasion from the routine. Use wax for the five wedding invitations or the handwritten letter. Use a stamp for anything you do weekly. A self-inking logo stamp gives the same sense that the item came from you, with none of the melting and cooling. The same artwork you would put on a wax matrix, such as initials, a crest or a simple emblem, can often be adapted to a stamp. If you are unsure whether your design will work at a small size, ask before you order. Simple shapes and clear lines reproduce best.
— Steven
Getting a seal-style mark of your own
If what you want is a round, emblem-style mark for envelopes, favours or packaging, there are practical options in our range:
- A 25mm personalised logo stamp gives a compact seal-sized impression from your own artwork.
- A 42mm round personalised logo stamp suits a larger emblem.
- A personalised wedding wreath stamp carries names and a date for invitations and favours.
- Personalised packaging stamps mark boxes and bags for small shops.
For the full range, browse our personalised logo stamps, or use the stamp finder if you are not sure which size you need. For help preparing artwork, see the custom stamp design process guide.
The same engraved-mark thinking applies beyond paper. Brands that want to carry an emblem onto textiles often use custom woven labels, which is another way a single design can be reproduced consistently.
Common misunderstandings
“A wax seal is a stamp.” Strictly, the seal is the impression and the tool is the matrix. In everyday shopping the words are used loosely.
“Sealing wax is beeswax.” Medieval wax was; most modern sticks are shellac-based, as the Lincoln project notes above.
“Wax must be boiling hot.” It should be molten but allowed to cool slightly before you press.
“Wax seals are legally binding.” Not in everyday UK correspondence. Historically they authenticated documents, but today a signature or other formal process does that work. The main current formal use we found is on diplomatic bags.
“Owners sealed their own letters.” Often staff did it, according to the Aberystwyth research cited earlier.
Frequently asked questions
What is a wax seal used for today?
Mostly for decoration on invitations, letters, cards and gift wrapping. It signals care and formality rather than proving anything. A formal functional use remains on diplomatic bags, which must carry a seal in wax, metal or plastic.
What is the wax seal called?
The impression in the wax is the seal. The engraved die that makes it is the matrix, often sold as a wax seal stamp. Archivists keep the two terms separate, though many people use “seal” for both.
Are wax seals still used?
Yes, but chiefly as a decorative finishing touch. They no longer authenticate ordinary correspondence in the UK, where a signature does that job. Many people now choose a self-inking stamp for repeated business use and keep wax for special occasions.
Can you post a letter with a wax seal?
It is possible, and many people do, but brittle wax can crack in automated sorting. Use a flexible sealing wax, keep the seal small and flat, and protect important items with an outer layer.
How do you stop wax sticking to the stamp?
Let the wax cool slightly before pressing, so it is tacky rather than runny. A very light film of oil or moisture on the matrix can also help release it cleanly.
Sources
- Seals, The National Archives
- Handling seals, The National Archives
- The history and conservation of seals, Surrey County Council
- A Crash Course on Wax Seals, Essex Record Office
- On Making Wax Seals, First Impressions, University of Lincoln
- Authentication of legal and administrative documents, University of Nottingham
- Making an Impression: palm prints on medieval wax seals, Aberystwyth University
- DIPPRIV2200 Diplomatic bags, HMRC internal manual, GOV.UK
- Can you send envelopes with wax seals safely?, Postcrossing Community