How much weight can a zip tie hold? It depends on the width. Our nylon zip ties break at 8kg for a thin 2.5mm tie, 22kg for the everyday 4.8mm, and 80kg for a 9mm tie. Length makes no difference to strength; it only decides how big a bundle the tie can go around.
Those numbers are breaking strains: the load at which the tie snaps. This guide gives the full table, explains why you should never load a tie close to its breaking strain, and covers what weakens a tie over time.
Breaking strain by width
| Width | Breaking strain | In pounds (approx.) | Lengths we stock | Good for |
|---|---|---|---|---|
| 2.5mm | 8kg | 18lb | 100 to 200mm | Single leads, small looms, tags |
| 3.6mm | 18kg | 40lb | 150 to 300mm | Household jobs, light looms |
| 4.8mm | 22kg | 49lb | 200 to 450mm | Wiring, conduit, fencing mesh |
| 7.6mm | 55kg | 121lb | 200 to 750mm | Heavy bundles, steel, signs, pipe |
| 9mm | 80kg | 176lb | 530 to 1220mm | Oversized bundles, hose and pipe |
| 12.6 to 12.7mm | See pack | 230 to 730mm | Fat looms, hydraulic hose |
Imported ties and overseas guides often quote strength in pounds (for example "50lb" or "120lb ties"); the pounds column lets you compare. White, black and coloured ties of the same width have the same breaking strain. Releasable ties are 7.6mm and also 55kg. Where it says "see pack", the strength is printed on the pack.
Breaking strain is not a safe working load
A breaking strain is the point of failure under a steady pull in good conditions. Real jobs are rarely that kind. As a rule of thumb, we suggest choosing a tie whose breaking strain is at least double the load it will carry, and more when:
- The load moves or vibrates. A bundle on a trailer or machine shakes the tie thousands of times a day.
- The tie sits over a sharp edge. A burr on steel can cut into a nylon strap well below its rating.
- The tie lives outdoors for years. Sun and heat slowly reduce the strength of any plastic.
- Failure would hurt someone. Zip ties are holding fasteners. Never use them to lift, hang or restrain anything where a snap could cause injury.
How to get more holding power
- Go wider, not longer. A 4.8 x 450mm tie is no stronger than a 4.8 x 200mm one. Step up to 7.6mm for 55kg.
- Use more than one tie. Two or three ties spaced along a bundle share the load and keep it from twisting.
- Tension it properly. A loose tie lets the bundle move and chafe. A zip tie gun pulls every tie to the same tension.
- Protect the strap from edges. Pad sharp steel, or use a wider strap that spreads the pressure.
- Switch material when conditions are harsh. Near heat, salt or chemicals, use stainless steel zip ties, rated to approximately 538°C.
What weakens a zip tie
- Sunlight. Ultraviolet light breaks down plastic over time. Our black ties are UV stabilised, but nothing plastic lasts forever in full sun.
- Heat. Nylon softens as it gets hot. Keep nylon ties away from exhausts and engine parts.
- Cold. Nylon gets stiffer in cold weather, so fit ties carefully and avoid sharp bends on a frosty morning.
- Damage. A nick in the strap or a tie that has been opened and closed many times will fail early. Replace it.
Which are the strongest zip ties?
In our nylon range, the 9mm ties are the strongest published rating at 80kg, in lengths up to 1220mm. The 12.6 and 12.7mm ties are wider still, for fat looms and hose, and their strength is printed on the pack. Where heat, corrosion or fire matter more than raw pull, stainless steel is the stronger choice overall. For a side-by-side look, see metal vs plastic zip ties.
Looking for ties for a tough job? Our heavy duty zip ties start at 7.6mm and 55kg.
Common questions
How much weight can a zip tie hold?
From 8kg for a 2.5mm tie up to 80kg for a 9mm tie, measured as breaking strain. Plan to load a tie with no more than half of that, and less if the load moves.
Why are zip ties so strong?
Nylon 66 is a tough, slightly flexible plastic, and the pawl in the head locks across the full width of the strap. A wider strap adds more material, which is why strength rises with width.
Can zip ties hold a car bumper?
They are often used to hold a loose bumper or undertray until it can be repaired, but that is a temporary fix. Use several 7.6mm ties, and have the clips or brackets replaced properly.
Do zip ties get weaker over time?
Yes, slowly. Sun, heat and repeated movement all wear a plastic tie. Check ties on outdoor and moving jobs, and replace any that look faded, cracked or nicked.
Does a longer zip tie hold more?
No. Strength comes from width. Length only changes the bundle size the tie can close around. See the zip tie sizes guide to match length to bundle.
Written by the team at Zip Tie Man, an Australian zip tie supplier since 2016. The breaking strains in this guide are taken from our own product listings.