NFC tags vs QR codes for guard patrols

How-to Published 9 February 2026 · 6 min read

If you are fitting checkpoints this week, this is the decision in front of you. Both work, both are cheap, and the right answer for most sites is a mix. Here is how to decide point by point.

The one-paragraph answer

NFC tags

An NFC tag is a passive chip in a plastic disc or sticker, usually 25–30mm across. There is no battery and nothing to maintain. The guard holds their phone near it and the app registers the point.

Where NFC wins

• Darkness. No camera, no aiming, no torch. This matters more than anything else on a night patrol.
• Speed. Well under two seconds, and it works through gloves.
• Weather. Outdoor-rated tags are sealed and survive rain, mud, frost and UV for years.
• Proof. The phone must physically be at the tag. There is no photographing it from the car.

Where NFC loses

• Costs money — a few pence for indoor stickers, up to around 50p each for rugged outdoor tags.
• Does not stick well to bare metal unless you buy on-metal tags, which cost more.
• Fitting takes slightly longer, since you are usually screwing or industrial-taping something down.

QR codes

A QR code is a printed pattern the phone camera reads. You generate it in the system, print it, laminate it and fix it in place.

Where QR wins

• Cost. Effectively free. You can cover a whole building for the price of a laminating pouch.
• Replacement. Damaged, faded or vandalised? Reprint it in thirty seconds.
• Compatibility. Every phone with a camera reads it, including older handsets your officers may still be carrying.
• Volume. If you need forty checkpoints in a building, this is how you afford them.

Where QR loses

• Needs light. In a dark yard the officer has to hold a torch and a phone at the same time, which gets old fast.
• Slower — aiming a camera takes a few seconds longer than a tap.
• Paper degrades. Even laminated, an exterior code will not last a UK winter.
• Theoretically photographable. GPS stamping on each scan catches this, but NFC removes the question entirely.

GPS checkpoints — the third option

Not a physical thing at all: a pin on a map with a radius. The app confirms the officer was within it. Ideal for perimeters, car parks, compounds and short-term sites, and it lets you set up a whole site remotely in minutes. The trade-off is accuracy — GPS is unreliable indoors and the radius has to be generous enough to allow for drift.

A sensible mix for a real site

Here is how we would fit a mid-sized construction site:

• Main gate — outdoor NFC. Every patrol starts and ends here, in the dark.
• Compound and plant — outdoor NFC on the container, the generator and the fuel bowser.
• Site office and welfare — QR codes inside, laminated, cheap and easy to replace.
• Fence line corners — GPS points. There is nothing worth fixing a tag to, and drift does not matter across a large perimeter.
• Roof and scaffold access — outdoor NFC. High-risk, so you want the strongest proof.

That is roughly twelve checkpoints, costs under £10 in tags, and takes about ninety minutes to fit during a normal patrol.

Practical fitting tips

• Chest height. Officers should not have to crouch or reach in the dark.
• Out of casual view. Visible tags get picked at. Just inside a doorway beats on the front of it.
• On-metal tags for metal. Ordinary NFC tags do not work reliably on steel. Buy the on-metal type.
• Name them properly. "North gate — pedestrian" is a report line your client understands. "CP7" is not.
• Keep spares in the van. A replacement tag is a five-minute fix, and the checkpoint's history is preserved because the record belongs to the point, not the tag.
• Photograph each one when you fit it. Six months later, nobody will remember where checkpoint 9 is.

More on how checkpoint scanning works in SMS-Patrol, or book a demo and we will set up a sample site with you.