Stick Packs vs. Sachets: Choosing a Single-Serve Format

Stick packs and sachets both deliver a single serving in a small film pack, and both are made on form-fill-seal machines from reel film. From a distance they look like variations of one idea. In practice they differ in seal structure, in how the product is dosed into the pack, in how the consumer opens it, in how much film each dose uses and in how the packs are collected and boxed.

The right choice depends on the product, the consumer use and the plant, so the comparison below does not recommend one format in general. It treats multi-lane configuration as a specification question rather than a speed claim.

How each format is formed

Both formats start with film from a reel that is wrapped into a tube and sealed. The geometry of the seals is what differs.

Stick pack

A stick pack is a narrow, long pack. The film is formed around a small forming tube and its edges are joined with a back seal that runs along the length of the pack. The back seal is either a fin seal, where the inner surfaces of the film meet and are pressed together, or a lap seal, where one edge overlaps the other. Transverse jaws then make the bottom seal, product is dosed into the tube, and the top seal closes the pack and starts the bottom seal of the next one. A tear notch near the top seal lets the consumer open the pack by hand.

The result is a tubular pack with three seals: the back seal, the top seal and the bottom seal.

3-side-seal sachet

A 3-side-seal sachet is a flat pack. In one common arrangement, the film is folded lengthwise so the fold forms one edge, and seals close the other three sides, usually the top, the bottom and one side. The fold edge is not a seal. Other arrangements form the pack from two separate webs, but the principle of three sealed edges stays the same.

4-side-seal sachet

A 4-side-seal sachet is also flat, but all four edges are sealed. It is typically made from two webs, or from a folded web with an additional seal. With no fold edge, every side is a sealed edge. This structure is used where a flat, even pack with seals all around is wanted, for example for a wafer-like or flat insert product.

Multi-lane machines

Because the packs are small, many machines form several packs side by side. As the diagram notes, a multi-lane machine forms several packs per cycle. The film web is wide, and several forming tubes or sealing stations run across it. The web is then cut into individual packs or into continuous strips.

Conditional comparison

The table lists the main decision points. Read each cell as “suits when” under that condition, not as a rule.

Decision point	Stick pack suits when…	Sachet (3-side or 4-side seal) suits when…
Dose and product	The product is a free-flowing powder, granule or thin liquid that can be tipped out in a narrow stream	The product is a paste, gel, cream, wipe-like or flatter item, or the dose is wider than a narrow tube can handle well
Opening	A tear notch and pour-out use fits the consumer	A tear notch or a cut-open edge on a flat pack fits, and squeezing out a paste is expected
Print area	A narrow, tall print panel is enough	A larger flat panel is needed for text, graphics or promotional space
Film use	The pack has a tubular layout with fewer seal edges in many cases	The pack may use more film for the seal margin around the dose; the actual film use per dose depends on the dimensions and seal width
Shape and display	Packs are stood upright in a tub or dispenser, or lined up in a carton	Packs lie flat in a carton, are stuck to a card or are inserted in another pack
Cartoning	Sticks are counted into bundles or stacked and fed to a cartoner	Flat sachets are stacked or shingled and fed to a cartoner
Machine configuration	Lane count and pitch are set by the pack width and the web	Lane count and format size are set by the pack width and cutting method
Format changes	Changing dose or length means changing forming tubes, jaws and the cut length	Changing size means changing forming parts, jaws and the knife or cutting system

Dose and filling

Single-serve packs put the dosing question up front. A dose can be filled by volume, for example with a volumetric cup or an auger, by weight, or by a pump or piston for liquids and pastes. Filling method matters more as the dose gets smaller, because relative variation in a small dose can be larger than in a bigger pack. Our comparison of auger fillers and multihead weighers covers matching the dosing principle to the product, and the same principles apply to dose heads on multi-lane machines. For small doses, specify the dose as a quantity with the product’s bulk density or form stated, and ask the supplier how the dose will be verified instead of relying on a general claim of accuracy.

Opening and consumer use

Opening is a design choice. A tear notch, a laser score, a pre-cut or a straight tear all work with different film structures, and a film that tears cleanly in one direction may not suit another. If a notch is needed, confirm with the film supplier that the film supports it, and ask the machine builder how the notch is made. Child-resistant or senior-friendly features are a pack design topic that depends on the product and the market, and they are outside the scope of this guide.

Film and seal considerations

The seal structure affects which tests apply. A back seal and two transverse seals form a tube, while a sachet has an edge seal around the perimeter. Seal strength can be measured with an agreed test method, for example one from the family of standard test methods for seal strength of flexible barrier materials, and the user sets the acceptance level. Film layers, seal layer and sealing window affect both formats. See the guide on film and machine compatibility for the film properties that matter on the machine.

Small packs filled with powder or oily products can have product in the seal area, which weakens the seal. That risk is part of why seal investigation methods exist. See investigating seal defects.

Relation to other bag-forming machines

Stick pack and sachet machines are specialized form-fill-seal machines. Larger pillow or gusseted bags are formed on vertical form-fill-seal machines, and finished pouches on premade pouch machines. The guide to VFFS and premade pouch machines compares those two.

Multi-lane configuration as a specification question

Multi-lane machines are a practical way to make small packs, but the lane count is a specification decision tied to everything upstream and downstream. It should not be presented as a speed figure without the conditions behind it.

Questions to settle with the supplier:

• What is the rated speed, and how is it expressed? Ask for cycles per minute and packs per cycle separately, and for the product, dose, film and pack size the rating applies to. The pack rate is the cycle rate multiplied by the number of lanes, but only when every lane can be filled and sealed at that cycle rate.
• How is each lane dosed? Options are one shared doser, a doser per lane or a multi-outlet dosing head, and the choice affects dose consistency between lanes and cleaning effort.
• How is dose consistency across lanes verified? Lanes can differ because of product distribution, tooling wear or seal pressure, so ask how lane-to-lane differences are detected and corrected.
• What happens when a lane fails or is shut off? Some machines allow operation with fewer lanes, and others require a format change. Ask how the machine handles a faulty lane and how output is affected.
• What is the pack pitch, and how does it limit lane count? Pitch is the distance between packs across the web. Web width, tube size and pack width together limit the number of lanes.
• How are packs collected downstream? Many packs per cycle need a collating system, such as a conveyor, counting, stacking or a feed to a cartoner. Counting and orientation affect cartoner performance, which the guide to cartoners and case packers covers.
• How is changeover handled? More lanes mean more tooling to change or adjust.

Questions to ask suppliers

Information to request or provide before comparing quotes:

• Product description: bulk density or viscosity, particle size, stickiness, dust, oil content, hygroscopic behavior, and any temperature sensitivity, with samples.
• Pack drawing: format (stick pack, 3-side or 4-side sachet), dimensions of the sealed pack, seal widths, seal type (fin or lap for sticks), tear notch or cut-open feature, and print registration needs.
• Dose requirement stated as a target quantity with a tolerance defined by you, and the method by which the supplier will verify the dose.
• Film specification and the supplier’s film requirements: structure, thickness range, seal layer, coefficient of friction, reel width and core size.
• Lane count and pack pitch, rated speed with its conditions, and the maximum and minimum pack size range.
• Dosing method per lane, and how the supplier handles dust or product in the seal area.
• Downstream configuration: counting, collating, stacking, cartoning or bundling method.
• Format change steps and parts, and the expected effort.
• Safety and compliance documents: risk assessment basis, guarding concept, and the references the machine is designed to. Relevant references include EN 415-3 for form-fill-seal machine safety and EN 415-10 for general packaging machine safety in the EU, depending on the market and product.
• Spare and wear parts list, such as sealing jaws, cutting knives and forming tubes.

A packaging machine RFQ checklist can be used to organize these items into a complete request.

Checklist before choosing a format

• Product form and dose are defined, with the dose method (volume, weight or pump) agreed.
• Opening method and consumer use are described, including any tear notch or easy-open feature.
• Pack drawing shows the seal structure and the print area.
• Film specification is confirmed with the film supplier for the chosen format.
• Lane count and rated speed are stated with their conditions.
• Dosing arrangement per lane and lane-to-lane verification are agreed.
• Downstream collating, cartoning or bundling is specified.
• Changeover scope is understood for every size you plan to run.
• Safety documents and guarding concept are requested.
• A trial with real product and film is planned before acceptance.

Limits and on-site verification

This guide cannot select a format or lane count for your product. These points stay open until you test:

• Dose performance depends on the product, the dosing method and the machine. Confirm it with real product, at the real dose, across all lanes.
• Seal strength, seal appearance and leak behavior depend on film, jaw settings, product contamination in the seal area and storage. Test with your film and agree on a test method and acceptance criteria.
• Opening and use need a check that the pack opens as intended and that product comes out as expected.
• Nominal pack rate is not sustained output. Downstream steps, product supply, film changes and stoppages all reduce it.
• Labeling, food contact and dose declaration requirements vary by market and product.

Related decisions

If the pack format is still open, see the comparison between VFFS and premade pouch machines. For the dosing method, read the guide to auger fillers and multihead weighers. For film questions, continue with film and machine compatibility.