Pozidriv and Phillips mix-up: which bit to use

DiagnosisOctober 20267 min read

A Pozidriv and Phillips mix-up rounds the screw head. Tick marks mean Pozidriv, a plain cross means Phillips, and the size still has to match.

Peter F. edits DIY & tools at productscompared.co.uk. Identification and damage notes come from Bolts.co.uk, Shop4Fasteners, BuildWiz and Wonkee Donkee. Supadriv and JIS stay inside the note ITS publishes. Prices and contents are amazon.co.uk listings in our bit-set group. We did not run a lab test, and we did not drive your screw. A qualifying purchase through our links can earn a commission at no extra cost to you.

In short

Tick marks between the arms of the cross mean Pozidriv. A plain cross means Phillips. A Phillips bit in a Pozidriv screw can cam out. A Pozidriv bit in a Phillips screw sits proud and damages the head. Match the family, then the size number, and stop once the recess starts to shine.

The tick-mark test

Hold the screw under a lamp. Tick marks on a screw are the four short lines in the angles of the cross, between the main slots. Bolts.co.uk uses those lines as the Pozidriv mark. A Phillips head is the cross alone. Extra lines on a clean head mean a bit stamped PZ. A head that is only a cross means PH.

The flanks agree when the marks are faint. Bolts.co.uk describes Pozidriv flanks as parallel and Phillips flanks as tapered, so a Pozidriv recess looks straighter-walled and a Phillips recess narrows as it goes down. If the screw has already been driven, read an unused screw from the same box.

PZ2 is Pozidriv size 2. PH2 is Phillips size 2. The digits match often enough that people treat them as one tip. They are a size inside a family. Pozidrive is the misspelling Bolts.co.uk notes. Pozidriv is the trade name, and both words point at the tick-mark cross. If the packet says Pozidrive, use a PZ bit after you have seen the lines. A cam-out scar can imitate an extra line, and paint can hide a real one.

What a Pozidriv and Phillips mix-up does

The two mistakes differ. A Phillips bit in a Pozidriv screw can turn it at low torque, and it can still damage the recess. That is the Bolts.co.uk account. Shop4Fasteners puts the design beside it: Phillips is designed to cam out, and Pozidriv is designed to stay seated. Cam out is the bit climbing out of the cross while the driver is still turning. The head shines because steel has wiped the corners.

That first successful turn is the trap. The screw moved until the thread tightened and the driver jumped. Leaning harder grinds the recess. On a chipboard screw already half home in a cabinet side, that grind can leave a head the correct PZ2 will no longer bite.

A Pozidriv bit in a Phillips screw fails earlier. It sits proud, the wings bear on the top of the recess, and the head tears. Bolts.co.uk gives this mix-up no low-torque workaround. More clutch will not draw a Pozidriv point down into a tapered Phillips cross. Stop at the first shine. A matched bit sits down until the shank nearly meets the head. If you only own a PH2 and the screw shows tick marks, leave it until you have a PZ2.

The fuller split of the two recesses is on Pozidriv or Phillips. Clutch, angle and speed, once the family is right, are on how to use screwdriver bits.

Match the size after the family

Family first, then the number. A PZ1 in a PZ3 recess slops. A PZ3 in a PZ1 recess sits on the rim and tears it, the same proud fit as a Pozidriv bit in a Phillips head. The tick-mark test misses that error because both bits are already PZ.

BuildWiz puts PZ2 on screws of about 3.5 mm to 5.0 mm, roughly No.6 to No.10 in their wording, and PZ3 from about 6 mm. Wonkee Donkee’s table calls a 3.0 mm Pozidriv shank PZ1. Those are their guides, not a British Standard, and the table is for woodscrews, not machine screws. Thread diameter is not drive size. If the tip wobbles, step up. If it will not drop in, step down. A 4 mm woodscrew is a common PZ2 reach on that reading.

Plasterboard is the usual Phillips habit in a UK pile. BuildWiz says PH2 often, if the box says Phillips. Chipboard and ordinary woodscrews sit the other way: the Bolts.co.uk recess guide treats Pozidriv as the common recess for both. A flat-pack cam in the same bag is often a different drive. Choosing the screw itself belongs on the wood screw comparison. If a new PZ2 seats and the old one rocks, the old one is finished. This page has no screw-count for tip life.

Sets that name only one cross

A large case can omit the family you need. The Amazon Basics 42-piece impact set is listed at £10.08, with 4.5 from 6,226 amazon.co.uk reviews. The contents name Phillips, slotted and Torx. Pozidriv is absent. The listing claims an impact-resistant design and S2 steel, with bits at 25 mm and 50 mm. Those points matter for Phillips or Torx on an impact driver. They do not add a PZ2.

The Bosch 32-piece extra-hard set, model 2607017319, is the top pick in the bit set comparison for a first combi drill. The listing shows £8.36 and 4.7 from 26,022 reviews, with two PH2 and two PZ2, plus PZ1, PZ3, PH1 and PH3, at 25 mm on a 1/4 inch hex and a magnetic holder. It is described for drill drivers, not as an impact set. One reviewer says the PH2 bits break quite easily, others describe a case that cracks, and the warranty field says no warranty.

The Bahco 59/S100BC is £19.43 with 4.7 from 979 reviews and names both drives, but the piece-count field says 1 against a 100-piece title, so read the contents for spare PZ2 tips. The Faithfull 61-piece set, FAISBSET61, is £8.99 with 4.6 from 240 reviews, and the best-value pick after the Bosch set, with three PZ2, three PH2 and a 60 mm adaptor. Breakage, a wonky holder, damp-storage rust, and a drive-system field that says Phillips only while the contents name Pozidriv all cut that score. Milwaukee’s text here names Torx, Phillips and hex, so piece count can still omit PZ2. Who should skip the Bosch case is on the best bit sets in this group.

Stop when the recess shines

Seat the bit by hand before you pull the trigger. A matched bit drops in and stands square. A Pozidriv bit on a Phillips screw stands high. A Phillips bit in a Pozidriv screw may sit down and still cam out once the screw bites, so drive one turn and look. Dull metal, with the bit still seated, means continue. A bright ring in the cross means change family or size.

Keep the clutch low enough that a slip happens before a tear. That is workmanship, not a lab setting. An impact driver makes the same mix-up faster. The Amazon Basics set above is described for impact drivers and still omits Pozidriv, so impact-rated steel belongs in a recess that already matches. Leave a round head alone. This page has no extraction method, and a structural or seized screw can be a job to hand on.

Supadriv, on the ITS note, can use the same driver as Pozidriv, so that name does not add a third bit. JIS is a different cross, and a Japanese appliance is a reason to stop rather than reach for PZ2. Carry both families if you have tick-mark woodscrews and plain-cross plasterboard screws. The Bosch 32-piece set is the top pick here because the contents name both, with the case and warranty limits above. A set that omits Pozidriv is a fair omission only when this job is Phillips or Torx.

Common questions

What are the little lines between the cross?

Those lines are the tick marks that mark a Pozidriv screw. They sit in the angles of the cross, as four short extra marks. A Phillips head is a plain cross, without those marks. Bolts.co.uk uses that split, and the same page describes Pozidriv flanks as parallel and Phillips flanks as tapered. Look at the screw, not the bit already in the chuck. A worn head can hide the marks, so check a fresh screw from the same box if the first one is already shiny.

Will a PH2 bit turn a PZ2 screw?

It can turn a Pozidriv screw at low torque, and it can still damage the head. Bolts.co.uk makes that point about a Phillips bit in a Pozidriv recess. Phillips is designed to cam out, which is the point Shop4Fasteners makes, so the bit climbs out once the screw gets tight. PZ2 and PH2 share a size number. They do not share a recess. If the head starts to shine, stop. A second push with the same PH2 bit makes the next attempt worse.

Why did the head tear when I used a Pozi bit?

A Pozidriv bit in a Phillips screw does not seat. It sits proud and tears the head, which is the other half of the mix-up Bolts.co.uk describes. The bit looks as if it has gone in, because both shapes are crosses, then the wings of the Pozidriv tip bear on the tapered Phillips recess. More trigger pressure does not pull it down. Take the bit out, look for tick marks, and fit a Phillips bit of the same size number if the cross is plain.

Is Pozidrive a real name?

Pozidriv is the trade name. Pozidrive is the common misspelling, which Bolts.co.uk notes. Listings, box ends and forum posts use both, and they mean the same recess when the writer is talking about the tick-mark cross. The stamp on the bit is still PZ, not a third family. If a title says Pozidrive No.2, read it as PZ2 and then check the screw for the extra lines. Spelling does not change the rule that a Phillips bit is the wrong fit.

Are chipboard screws Pozidriv?

Pozidriv is the common recess on woodscrews and chipboard screws, on the Bolts.co.uk recess guide. That is a habit of the UK trade, and it is still a check you make on the head. Look for the tick marks before you pick PZ2. A box can mix drives, and a furniture cam bolt in the same packet is often a different recess. The guide is about the recess you usually meet. It is not a promise that every chipboard screw in the shed follows it.

Do I need both bits in the box?

Yes, if the job mixes woodscrews and Phillips screws. UK chipboard and many woodscrews are Pozidriv. Plasterboard screws are often Phillips when the box says so. A set that names only Phillips leaves the tick-mark screw without a matching tip. The Bosch 32-piece extra-hard set, the top pick in our bit set comparison, lists two PH2 and two PZ2. A box that names one family is fine for a single job, and it is a gap the moment the next screw is the other cross.

Is a drywall screw PH2?

Often, when the box says Phillips, and that is BuildWiz’s guide rather than a British Standard. PH2 is the size they associate with that drive. Confirm the word on the box, then confirm a plain cross on the head. A Pozidriv bit will sit proud in that recess and tear it. If the box is unlabelled, use the tick-mark test and stop if the bit does not sit flush. Do not treat every plasterboard screw in a mixed tub as PH2 because the last box was.

What is Supadriv, and is JIS the same cross?

Supadriv can use the same driver as Pozidriv, on the account ITS publishes. You do not have to buy a third bit for a Supadriv screw on that reading. The limit is theirs: this page is not a Supadriv specification. JIS is a different cross. Do not fold a Japanese Industrial Standard screw into the Pozidriv tip because both look like a cross at arm’s length. If the screw is marked JIS, or it came with a Japanese appliance, the Pozidriv bit is the wrong assumption.

Peter F.

DIY & tools

Peter F. is the editor for DIY & tools at productscompared.co.uk. Comparisons in this category are checked against amazon.co.uk listings, review evidence and public UK sources.

Updated: October 2026

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When to stop on a stripped screw

More force makes the next step worse. Some screws are not a job to finish with the same bit.

Matching a bit to a wood screw

Gauge and drive both have to match. A box of woodscrews and one cross-head bit is not a full kit.