A custom mylar envelope is a flat sleeve of laminated film, sealed on two or three sides, that holds thin items without the bulk of a gusseted bag. TBPB prints envelopes with your artwork and prepares the dieline, and you approve a free digital proof before anything is printed.
What a mylar envelope is built from
Most mylar envelopes are laminates of three kinds of layer: a printable outer film, a barrier layer such as metallized film or foil, and an inner layer that melts to form the seal. The barrier layer is what separates an envelope from a plain poly mailer. It cuts light and slows the passage of moisture and oxygen, which matters for samples, sachets, dried goods and printed inserts that should stay crisp. No flexible laminate keeps out air forever, so if your product needs a shelf life figure, get it from your own testing rather than from a bag description. Tell us what goes inside and ask which structure suits it.
Envelope, flat pouch or stand up bag: how to choose
The three formats overlap, so choose by the thickness of what goes inside and by where the package will be seen.
| Mylar envelope | Flat pouch | Stand up mylar bag | |
|---|---|---|---|
| Shape | Flat sleeve sealed on two or three sides | Flat pouch, usually sealed on three sides | Folded bottom gusset lets the bag stand |
| Best for | Inserts, sachets, seed packets, film | Samples and single servings with a little depth | Retail shelves and larger fills |
| Contents | A few sheets thick at most | Thin to moderate | Bulky or loose products |
| On display | Lies flat or hangs | Lies flat or hangs | Stands and shows its front panel |
| Mailing | Slips into a mailer or a larger order | Stays flat when thinly filled | Bulkier, usually boxed |
| Watch for | Corners bulge once the contents have thickness | Less shelf presence than a stand up bag | The gusset uses film and height, so size it with real product |
If your item has real volume, compare flat pouches and stand up mylar bags. For single servings that need a little depth, see small mylar bags, and for fine powders or items where the air must be removed, look at mylar vacuum seal bags.
Sizing a flat envelope
- Measure the item at its widest and longest points and note its thickness.
- Add the seal border on every sealed edge.
- If you want a zipper or a tear notch, add room above the item for it.
- Allow a little slack so the item slides in without bending its corners.
- If the item is thicker than a few sheets of paper, compare a flat pouch or a stand up bag instead.
Send those measurements with your request. We prepare the dieline from them and show the layout on your free digital proof.
Closures and opening
A heat sealed top closes the envelope permanently and needs a sealer on your side. A press-to-close zipper lets customers reopen the envelope, which suits samples used over several days, and a mylar ziplock bag suits goods that are opened again and again. A tear notch gives a clean first opening without scissors. A clear window shows the contents but lets light in, so use one only when the product does not need light protection. Ask which closures, notches and windows are available for your envelope size.
Shipping flat without damage
A flat envelope protects against light and moisture but does little against a crushed corner in a sorting machine. For documents, film and anything that must stay flat, ship the envelope inside a stiff mailer or between two pieces of board. For samples that travel inside a larger order, the envelope usually needs no extra stiffener. Think about how the recipient opens it too: a tear notch near the top saves a pair of scissors and keeps the tear away from the printed face.
What we confirm on every order
| Printing | Printed with your artwork |
|---|---|
| Sizing | Sized from the measurements you send |
| Dieline | We prepare the dieline for your size |
| Proof | Free digital proof. Nothing is printed until you approve it |
| Quantity | Short production runs are available. Tell us the quantity you need |
| Pricing | Quote based. Request a quote for pricing and timing |
| Sample kit | Free kit of stock boxes and materials so you can compare options. It is not printed with your artwork. Ask whether it includes mylar film samples |
| Size range, film, closures, window, finish | Ask in your quote request. We confirm what is available for your envelope size |
| Food contact | Yours to confirm with your regulatory adviser. TBPB makes no certification claim |
What to send for a quote
- The item: what it is and its flat width, length and thickness
- Closure: heat seal, press-to-close zipper or not sure yet
- Extras to ask about: tear notch, hang hole, window, corner style
- Print on one side or both, and whether your artwork is ready
- Finish you prefer: matte, gloss or not sure yet
- The quantity you need and the date you need the envelopes
If the envelope will hold a food, supplement or cosmetic, the labeling and contact material requirements are yours to confirm with your own regulatory adviser. TBPB prints the artwork you supply. Use the quote form on this page or the button below, or call 540-808-0830, to request a quote for pricing and timing, and browse the full mylar bag range to compare shapes.
Request a quote for mylar envelopes
Frequently asked questions
What is a mylar envelope used for?
A mylar envelope holds thin, flat items that benefit from protection against light and humidity: product samples, printed inserts, film, seed packets and single sachets. It lies flat, slips into a mailer or a larger order, and carries your branding on the face. If you ship electronic parts, ask whether an anti-static film is available.
Can I order a small quantity of custom mylar envelopes?
Short production runs are available. Tell us the quantity you need in your request and we quote it. Send the flat item dimensions and the closure you want, and we include them in your quote.
How do I choose the right envelope size?
Measure the item at its widest and longest points, then add the seal border on each sealed edge and a little slack so it slides in easily. If the contents have noticeable thickness, a gusseted pouch is a better fit than a flat envelope. We prepare the dieline from your measurements.
Can I get a resealable closure?
Ask about a press-to-close zipper if customers will reopen the envelope, for example samples used over several days. A heat sealed top closes it permanently and needs a sealer. Tell us how the envelope will be used and we confirm the closure options for your size.
Are mylar envelopes waterproof?
A metallized or foil barrier laminate slows water vapor, so mylar style envelopes handle humidity well, but no flexible envelope should be treated as fully waterproof. Seams, punctures and open edges can still let moisture in. If your product must stay dry in difficult conditions, tell us and ask which structure suits it.
Can the envelope have a clear window?
Ask whether a window is available for your size. A window shows the contents but lets light in, which defeats part of the barrier, so it suits products that are not light sensitive. For anything that is, choose a fully printed, opaque envelope.
More Mylar Bags
See the full Mylar Bags range, or explore related options with no minimum order and our best-price guarantee:
