What's the difference between auto-bottom, tuck-end, and seal-end boxes?

Auto-bottom (4-corner-glue) pops open with a locked bottom in one motion — fastest to assemble and holds heavier loads. Tuck-end has folded tabs at top and bottom, cheapest to make but slowest to hand-assemble and lower load rating. Seal-end glue-seals both ends at manufacture — tamper-evident, sealed shut until the customer opens it. Pick based on assembly speed, load, and whether you need tamper-evidence.

When should I use an auto-bottom box?

Use auto-bottom when you assemble in-house at volume (500+ boxes/week), the product weighs over 1 lb, or the bottom needs to lock without tape. Common uses: bakery gift boxes (cupcake, macaron, chocolate), DTC gift boxes, apparel retail, and any mailer that holds a heavier product. Costs ~$0.05-$0.10 more per unit than tuck-end but saves 5-15 seconds per box at assembly.

When should I use a tuck-end box?

Tuck-end is the cheapest and most common — use it for lightweight products (under 1 lb), single-SKU cosmetic and skincare cartons, small food packaging, and any application where per-unit cost matters more than assembly speed. Reverse tuck-end (opposite-side tucks) is the workhorse for cosmetics; straight tuck-end (same-side tucks) is common for retail.

When should I use a seal-end box?

Use seal-end when the box must arrive sealed (retail SKUs at big-box), you need tamper-evidence (OTC drugs, dietary supplements, cosmetics), or the product is small/loose enough that an unlocked tuck flap would let it fall out. Common uses: OTC medicine, dietary supplement cartons, dry food, and cosmetic starter kits.

Which structure is best for OTC drug and pharma packaging?

Seal-end. FDA guidance for OTC drug cartons requires visible tamper-evidence at both ends, and seal-end's glue-sealed closure delivers exactly that — any prior opening leaves a torn or peeled seal that shoppers and retail restockers can see. Add a shrink band around the closure for extra security.

Which structure is best for bakery and food packaging?

Auto-bottom for gift-tier bakery items (cupcakes, macarons, chocolate, cake pops) where load-bearing and fast in-house assembly matter. Standard tuck-end for lightweight bakery items sold at counter (cookies, pastries, bagged snacks). Seal-end for dry food SKUs that ship to retail where tamper-evidence is required.

Auto-Bottom vs Tuck-End vs Seal-End: Which Box Structure Fits Your Product?

By the Custom Box Printing Editorial Team · July 27, 2026

Auto-bottom, tuck-end, and seal-end are the three most common paperboard folding-carton structures used in US custom packaging. Each solves a different problem: auto-bottom optimizes for assembly speed and load, tuck-end optimizes for cost, seal-end optimizes for tamper-evidence. If you're a US brand founder or packaging manager picking a carton structure for a new SKU, this guide walks through the practical trade-offs so you pick right the first time.

Quick comparison

Auto-bottom (4-corner-glue / crash-bottom): Fastest hand-assembly (one motion pops open with locked bottom), holds heavier loads, costs ~$0.05-$0.10 more per unit than tuck-end.
Tuck-end: Cheapest to manufacture, slowest to hand-assemble, lower load rating, ideal for lightweight small-format packaging.
Seal-end (straight-tuck-seal): Glue-sealed at both ends by the manufacturer, delivers tamper-evidence, required for OTC drugs and many retail-shelf SKUs.

Auto-bottom: pop open, lock at the base

Auto-bottom (also called 4-corner-glue or crash-bottom) construction has four flaps at the bottom pre-glued at manufacture. When the flat carton is squeezed open, the bottom locks itself into a rigid base in one motion — no glue-gun, no tape, no manual folding.

When to use auto-bottom

You assemble in-house at 500+ boxes/week (bakery, gift-set assembler, DTC fulfillment).
The product weighs more than 1 lb and needs a locked bottom for transit.
The customer sees the box (a clean locked bottom reads more considered than a taped bottom).
Common applications: cupcake, cake pop, macaron, chocolate, gift boxes, mailer boxes holding heavier products.

Cost and load

Standard auto-bottom in 20pt SBS runs ~$1.15 per unit at 500. Load rating: 3-5 lb comfortably in 20pt SBS, 5-8 lb in 24pt SBS, 8-15 lb in corrugated E-flute. See custom auto-bottom boxes for full specs and pricing.

Tuck-end: cheapest, most flexible

Tuck-end is the classic folding carton — cardstock with folded tabs at the top and bottom that tuck into slits to close the box. Two main variants:

Reverse tuck-end (RTE): Top and bottom tuck from opposite sides. The default for cosmetics, skincare, and most small-format primary packaging.
Straight tuck-end (STE): Top and bottom tuck from the same side. Common for retail SKUs where hang-tab presentation matters.

When to use tuck-end

The product is lightweight (under 1 lb).
Per-unit cost matters more than assembly speed.
The customer opens and closes multiple times (tuck flaps re-tuck; auto-bottom and seal-end are single-open formats).
Common applications: serum, lipstick, lip balm, supplement, cosmetic, ampoule, toner, essence boxes.

Cost and load

Standard reverse tuck-end in 18pt SBS runs ~$0.85-$1.05 per unit at 500 depending on size and finishing. Load rating: 0.5-2 lb comfortably in 18pt SBS, 2-4 lb in 24pt SBS. See custom tuck-end boxes and reverse tuck-end boxes for full specs.

Seal-end: tamper-evident, sealed both ends

Seal-end (straight-tuck-seal) construction glue-seals both the top and bottom tuck flaps at the manufacturer. The customer opens the carton by tearing along a perforated line or peeling the glue-seal. Any prior opening leaves visible damage — the tamper-evidence signal every regulated category needs.

When to use seal-end

Tamper-evidence is required (FDA guidance for OTC drugs, many food and supplement retail SKUs).
The product must arrive sealed at retail (national-retail shelves at Target, Walmart, CVS).
The product is small or loose (tablets, pills, small hardware) that would fall out of an unlocked tuck flap.
Common applications: OTC medicine, supplement, capsule, softgel, dry food, cosmetic starter kits.

Cost and opening mechanism

Standard seal-end in 20pt SBS runs ~$0.95 per unit at 500. Opens two ways: tear-strip perforation (cleanest, most gift-worthy, +$0.03-$0.05/unit) or peel-away glue-seal (cheapest, most secure, included in base). See custom seal-end boxes for full specs.

Which structure fits your product?

Product	Best structure	Why
Lipstick / mascara / eyeliner	Reverse tuck-end	Lightweight, low cost, multi-open
Serum / ampoule / essence dropper	Reverse tuck-end	Snug bottle fit, low cost
OTC medicine / vitamin bottle	Seal-end	Tamper-evidence per FDA guidance
Cupcake / cake pop / macaron	Auto-bottom	Load-bearing, fast in-house assembly
Chocolate / candy / truffle	Auto-bottom or seal-end	Depends on gift-tier vs retail-shelf
DTC gift box (mid-weight)	Auto-bottom	Locked bottom, fast fulfillment
Small hardware / cosmetic accessory	Seal-end or blister card	Tamper-evidence at retail
Subscription outer carton	Auto-bottom or heavy tuck-end	Load-bearing for multi-SKU kits
Retail hang-tab SKU	Straight tuck-end + hang tab	Peg-wall compatible

All three ship flat

Auto-bottom, tuck-end, and seal-end are all folding cartons — they pack flat in bulk for freight, then fold or lock into shape at assembly. Flat shipping keeps freight cost low regardless of which structure you pick. A US-based printer can ship any of the three to any US state with 2-5 day Ground transit and free shipping.

Common combinations with hang-tab, window, and finishing

All three base structures can add:

Hang-tab at the top for retail peg display — see hang tab boxes.
Die-cut window on any panel with PET film patch to show product.
Foil stamping, embossing, spot UV, soft-touch lamination for premium finish.
Printed insert or divider to hold multiple SKUs upright (e.g. sampler boxes, coffee sample boxes).

How to pick for your product

Weigh the product. Over 1 lb → auto-bottom or corrugated. Under 1 lb → tuck-end or seal-end.
Check for tamper-evidence needs. OTC, supplements, retail-shelf food → seal-end.
Estimate in-house assembly volume. Over 500 boxes/week → auto-bottom saves 5-15 seconds per box.
Decide on retail context. Peg wall → add a hang-tab to a tuck-end or seal-end.
Request a 3D mockup. A US-based printer builds all three dielines free — see one in the format you're considering before you commit.

Ordering custom boxes — common questions

What is the minimum order for custom boxes?

Runs start at 100 units for folding cartons (cosmetic, food, bakery, CBD, mailer), 50 units for rigid setup boxes, and 5,000 units for printed paper (deli, butcher, tissue, kraft, sandwich wrap). No die, plate, or setup fees at any quantity.

Do you ship custom boxes free in the US?

Yes — standard shipping is free anywhere in the contiguous United States on every order. Rush production (3–5 business days) and expedited shipping are available for an additional fee.

How long does a custom box order take?

Typical timeline is 1 business day for a quote, 1–2 days to approve a free 3D digital mockup, then 7–10 business days for production plus 2–5 business days for free US shipping. Rush production is available on request.

Can I see a sample before I commit to a full order?

Yes — free 3D digital mockup with every quote, and a physical sample on request (refunded on your first order) before you place a production run. You can also design and preview your box live in our free 3D box designer.

What artwork files do you need to start printing?

Print-ready PDF, AI, EPS, or PSD at 300 DPI in CMYK with 0.125" bleed is ideal. Don't have artwork? Our in-house design team builds your dieline and preps files at no cost — just send your logo and any brand references.

Do you charge setup, plate, or die-cutting fees?

No — there are no setup, plate, die, or tooling fees at any quantity. Custom dielines, artwork prep, 3D mockups, and physical samples are all included free with every order.

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