Custom Clamshell Boxes
A clamshell is a box whose lid never comes off. It hinges at the back, folds over, and locks at the front — which means nothing to put down, nothing to misplace, and a pack that can be opened and closed with one hand.
- Build
- One-piece hinged clamshell; tuck tab, double tab or friction lip
- Board
- Folding boxboard or E flute; food-grade and grease-resistant available
- Hinge
- Single or double score, run across the grain where the layout allows
Get a price for Clamshell Boxes
Send the size and quantity — we reply the same working day with a price, a dieline and a date. Artwork optional at this stage.
- Free dielineThe flat drawing comes with the quote, before you commit.
- Proof before pressNothing is printed until you have seen it laid on the dieline.
- Die kept for reordersTooling is paid once. Every reorder skips straight to press.
- Quoted in four marketsUS, UK, Canada and Australia, in the delivery currency.
Where the hinge is, and why it matters
The hinge is a crease in the board, not a mechanism, so it never breaks in the way a plastic hinge does. What it does is soften: after enough openings the lid sits back a little further than it used to.
For a food pack opened once that is irrelevant. For a retail pack opened repeatedly on a shop floor, a double-scored hinge and a heavier board are worth specifying, because a clamshell that will not stay shut is a clamshell that gets replaced.
Score the hinge across the board grain wherever the layout allows. A hinge folding with the grain softens faster.
The front lock does the real work
A wide clamshell with a single central tab bows open at the corners. Above about 200 mm of width the lock has to be doubled or the box will not look closed even when it is.
| Tuck tab into a slit | Simplest and most common; holds well, opens easily |
|---|---|
| Double tab | Two locks across the front; for wider boxes that would gape |
| Friction lip | No tab at all; cleanest look, least secure |
| Adhesive seal or sticker | Tamper evidence; makes it single-use |
Food and retail want different things from it
If it is a hot food pack you are after, the venting and board decisions are in our burger and hot food packaging notes rather than here.
- Food clamshells need venting, grease resistance and heat retention.
- Retail clamshells need visibility, theft resistance and a hang hole.
- The two share only the construction, and nothing else about the specification.
- Trying to buy one pack for both usually produces something that suits neither.
The case against the plastic version
A sealed plastic clamshell shows the product completely and resists both theft and tampering. A board clamshell with a window shows most of the product, opens without scissors, and goes into a paper stream in one piece.
What it gives up is theft resistance, which is usually the retailer's requirement rather than the brand's. Whether that trade works depends on who you are selling through, and it is worth asking them before assuming.
Printing a box that is seen open
A clamshell spends much of its life open, with the inside of the lid facing up at the customer. That surface is in view during the whole time the product is being used or considered, and it costs a second print pass and no extra board.
On a food pack it is where a short message reaches every single customer. On a retail pack it is where the instructions belong, because that is where people will look for them.
Clamshell Boxes — specification
The rows that are specific to this build first, then what applies to every job we run. Anything not listed is a question, not a limit — send the brief.
This build
- Build
- One-piece hinged clamshell; tuck tab, double tab or friction lip
- Board
- Folding boxboard or E flute; food-grade and grease-resistant available
- Hinge
- Single or double score, run across the grain where the layout allows
- Windows
- Filmed or open die-cut
- Outer, inner lid and base
- Minimum
- 100 boxes
On every job
- Print process
- Digital below about a thousand, offset above it. One side or both, with spot colors where a match has to hold.
- Color
- CMYK as standard. Uncoated and kraft stocks print lighter and warmer; a spot color is the only exact match.
- Tolerance
- Cutting plus or minus 1 mm, creasing plus or minus 0.5 mm, confirmed on a plain sample before the run.
- Tooling
- A cutting die per size, made once and kept. Foil and emboss dies per artwork, also kept.
- Food contact
- Food-grade board and inks where the carton touches food, with the interior left plain.
- Sustainability
- Mono-material board wherever the product allows; recycled-content and FSC stocks; no claim printed the pack does not earn.
- Artwork
- Vector PDF or AI, 3 mm bleed, 4 mm safe area, fonts outlined. We check every file and send a proof before press.
- Dieline
- Supplied free with the quote, before you commit. Yours whether or not you order.
- Sample
- A plain unprinted sample at the finished size on request, for fit and construction.
- Reorders
- Skip the tooling and go straight to press at a lower unit price.
- Lead time
- Quoted with the price against your fill date rather than promised before we have seen the spec.
- Markets
- United States, United Kingdom, Canada, Australia — priced in the delivery currency, freight included.
Boards and films we build clamshell boxes on
A folding carton is one sheet of board, so the board is the product. These are the stocks we run for cartons, what each is good at, and where it lets you down.
Natural kraft
Unbleached folding board. Warm, hides marks, costs least. Mutes color — one or two flat colors print well, photographs do not.
250–350gsm sleeves; 14–24pt cartonsWhite SBS
Solid bleached sulfate: bright, coated, the retail carton standard. Takes accurate color and every finish. Shows scuffs sooner than kraft.
14–24ptWhite lined chipboard
A recycled gray core under a white printing face. Cheaper than SBS and slightly duller; the back of the sheet stays gray.
16–24ptKraft-look coated
A kraft face over a coated inner. The natural look with a barrier behind it — the answer where oil, grease or moisture would mark plain kraft.
14–20ptRecycled-content board
Post-consumer fiber with a gray-brown cast. Right for outers and inner components; poor for bright whites and photography.
16–22ptMicro-flute E and F
A fine corrugated layer where a carton needs structure it cannot get from board — a large panel, a heavy product, a box that ships alone.
E 1.5 mm; F 0.8 mmUncoated and textured
No clay coat, or a linen or laid grain. Print reads softer and warmer; a deboss goes deeper. Photographs do not sit well on it.
280–350gsmMetallised and pearlescent
A metallic or pearl face for a shelf that needs to catch light. Costly, and it fights a photograph — a mark or a pattern suits it better.
16–20ptNot sure which? Say what goes in it and where it is sold — the material follows from that. Our notes on recycled, recyclable and compostable cover which claims each stock can honestly carry.
- 01
Send what you have
A dimension, a photograph beside a ruler, or the product itself. No technical drawing needed — that part is ours.
- 02
We quote and draw
A price, a dieline and a date come back together. If a different build would suit the product better, that is in the reply too.
- 03
Approve the dieline
The flat drawing is yours to check: which panel is the front, where the folds fall, how deep the cavity really is.
- 04
Artwork on the dieline
You place your design on the flat we sent, or we place it for you, and you see a proof before anything goes to press.
- 05
A sample if you want one
A plain unprinted sample at the finished size shows fit and construction — the things a drawing cannot.
- 06
Cut, printed, shipped
The die is cut once and kept, so every reorder skips the tooling and goes straight to press at a lower unit price.
Format
Vector PDF or AI where possible. Raster artwork at 300dpi at final size, in CMYK.
Bleed
3 mm past every trim line, so a fraction of drift on the cutter never leaves a white edge.
Safe area
Keep type and anything important 4 mm inside the cut and away from every fold.
Color
Convert to CMYK before sending. Uncoated stock prints lighter; a spot color is the only exact match.
Fonts
Outline them or supply the files. A missing font substitutes silently and the proof will not match.
Barcodes
On a light, matte, unvarnished patch with the quiet zone clear — a code on gloss fails the scanner.
Not set up that way? Send it anyway — fixing a file is a short conversation, and we check every one before press. Our guide to preparing print files covers each point.
Every finish here is a decision about light on a shelf, not about luxury.
Matte lamination
Reads considered, hides marks, takes a ballpoint.
Gloss lamination
Lifts color; glares under shop lighting.
Soft-touch
Velvet in the hand; shows fingerprints in a bag.
Hot foil
Real metal leaf — the most reliable premium signal.
Emboss / deboss
Shape with no ink; works in the dark.
Spot UV
Gloss shapes on a matte field.
Uncoated kraft
Warm, natural, mutes color.
Textured stock
Texture in the paper; cannot scuff off.
Not sure which suits the shelf it sells from? Say where the product is sold and we suggest one — our notes on specialty finishes show them on real boxes.
Sizing a folding carton so the die comes out right: clamshell boxes
Measure the product, not the box it is in now. A carton is built around what has to fit inside it, assembled — cap on, lid fitted, folded if it folds — at its widest point in each direction. Send those three numbers and say which is which.
- Length x width x height
- Internal, always. External dimensions include the board and are what the carrier measures, not what the product needs.
- Clearance
- 2–3 mm a side for a snug fit; more where an insert or void fill goes in. A carton cut exactly to the product is slow to pack and transmits every knock.
- Board thickness
- Heavier board takes internal space from the product. It matters most on small boxes, where four walls of 24pt is a real share of the cavity.
- Varies between batches?
- Glass, textiles, molded parts and cured soap all do. Measure several and build to the largest.
- Cutting tolerance
- Plus or minus 1 mm on folding board. Confirmed on a plain sample before the run.
- Units
- Metric or imperial, as long as you say which. Mixing them in one spec is where mistakes happen.
Not sure your numbers are right? Send the product dimensions rather than the box dimensions and we work the box out — the full method is in our guide to measuring for a box.
Interactive · five steps · no sign-up
Build your Clamshell Boxes in 3D
Pick a shape, type a size, choose a board and a finish. The preview on the left redraws as you go, and the spec lands with us exactly as you set it.
Frequently asked questions
Got a question about clamshell boxes? The answers below cover what we get asked most. If yours is not here, send it with a brief, message us on WhatsApp, or call +1 503-461-4788 — we reply the same working day.
What is the minimum order?
100 boxes, food or retail build.
Will the hinge break?
It is a crease in board, so it softens rather than breaks. A double score and heavier board keep it crisp much longer.
Why does my clamshell gape at the corners?
One central tab on a wide box. Above about 200 mm the lock needs doubling.
Can a board clamshell replace plastic?
For visibility and easy opening, yes. What you give up is theft resistance — ask your retailer before assuming that is acceptable.
Is it suitable for hot food?
Only if specified for it — venting, grease resistance and the right board. That is a different build from a retail clamshell.
Can I print the inside?
Yes, and a clamshell spends much of its life open with the inner lid facing the customer.
Will the hinge break?
It is a crease in board, so it softens rather than breaks. For repeated opening, a double score and heavier board keep it crisp much longer.
Why does my clamshell gape at the corners?
One central tab on a wide box. Above about 200 mm the lock needs doubling.
Can I use a board clamshell instead of plastic?
For visibility and easy opening, yes. What you give up is theft resistance — ask your retailer before assuming that is acceptable.
Is it suitable for hot food?
Only if specified for it — venting, grease resistance and the right board. That is a different build from a retail clamshell.
Same range
