Screwdriver Bit Compatibility Guide
Not sure which screwdriver bit you need? You’re not alone — with Pozidriv, Phillips, Torx, hex, and dozens of sizes to choose from, picking the right bit for the right screw is one of the most common DIY and trade questions in the UK. This guide covers every major bit type, explains which bit fits which screw, and helps you avoid the most common mistakes.
The Most Common Mistake: PZ vs PH
If you’ve ever stripped a screw head and blamed the screw, there’s a good chance you were using the wrong bit. In the UK, most wood screws and construction screws use Pozidriv (PZ) heads — not Phillips (PH). The two look similar but have different geometry, and using a Phillips bit in a Pozidriv screw will cam out and damage the head. Our complete PZ vs PH guide explains exactly how to tell them apart and which to use when.
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PZ vs PH Explained
The single most important distinction for UK users. Learn to spot Pozidriv vs Phillips screws and choose the correct bit every time.
Which Bit for Which Screw
Master reference table covering every common screw type — PZ, PH, Torx, hex, slotted — matched to the correct bit type and size.
Impact Driver Bits
Not all bits can handle an impact driver. Find out which bits are impact-rated, how to spot them, and why standard bits shatter under impact.
Torx Screw Sizes
T10, T15, T20, T25, T30 — which Torx size for which application? Covers decking screws, automotive, electronics, and more.
Allen Key Sizes
Metric vs imperial, which size for IKEA furniture, and the full hex key size chart for UK applications.
Are Bits Universal?
All standard screwdriver bits use a 1/4″ hex shank — but that doesn’t mean every bit works in every driver. Here’s what to check.
Screwdriver Bits by Brand
Looking for bit recommendations for a specific brand of drill or impact driver? These guides cover which bits work best with each brand’s chuck system and include our recommended bit sets.
Quick Reference: Common Screw Types in the UK
Here’s a fast overview of the screw types you’ll encounter most often in UK DIY and trade work, along with the correct bit for each.
| Screw Type | Common Sizes | Correct Bit | Where You’ll Find It |
|---|---|---|---|
| Pozidriv (PZ) | PZ1, PZ2, PZ3 | PZ1, PZ2, PZ3 | Most UK wood screws, chipboard screws, construction screws |
| Phillips (PH) | PH1, PH2, PH3 | PH1, PH2, PH3 | Machine screws, electrical fittings, older screws, imports |
| Torx (TX/T) | T10–T40 | Torx T10–T40 | Decking screws, automotive, high-torque applications |
| Hex Socket (Allen) | 2mm–10mm | Hex bits or Allen keys | Flat-pack furniture, machine bolts, bike parts |
| Slotted | 4mm–8mm | Flat/slotted bit | Older fittings, electrical terminals, decorative hardware |
| Robertson (Square) | #1, #2, #3 | Square drive bits | Rare in UK — mainly Canadian/North American imports |
Understanding Bit Shanks
Almost every screwdriver bit sold in the UK uses a 1/4″ (6.35mm) hex shank. This is the universal standard that fits into drill chucks, impact driver chucks, bit holders, and magnetic extensions. The main variations you’ll encounter are bit length (25mm standard, 50mm, 75mm, 100mm, and 150mm) and whether the bit is impact-rated (torsion zone) or standard.
If you’re using an impact driver, you need impact-rated bits — standard chrome vanadium bits will shatter under the repeated hammering action. Look for bits labelled “impact”, “torsion”, or “FlexTorq” (Makita), “FLEXTORQ” (DeWalt), or “SHOCKWAVE” (Milwaukee). Our impact driver bits guide covers this in detail.