Geofenced clock-ins explained

A geofenced clock-in answers one question: was this person at the site when they said they started? It replaces the paper sign-in sheet and the phone call to a supervisor with a check the phone does in a second. Done well, it’s accurate, fair to staff and easy to explain. Done badly, it refuses honest people and annoys everyone. Here is how it works and how to set it up well.

What a geofence is

A geofence is an imaginary circle around a place: a centre point, usually the site’s address turned into coordinates, and a radius in metres. When someone clocks in, the app reads the phone’s position and the system checks whether it falls inside the circle. Inside, the clock-in is accepted. Outside, it’s refused, ideally with a message saying how far away the person is, so they know what went wrong.

In TDS Workforce Management, the position is read once at clock-in and once at clock-out, never in between. The clock-in record keeps the distance from the site and the accuracy the phone reported, so a manager can see how sure the check was.

How accurate phone location really is

Under open sky, a phone’s GPS is typically accurate to within about five metres. Accuracy drops indoors, underground, and between tall buildings, where signals bounce. Phones fill the gaps with Wi-Fi and mobile network positioning, which can be off by tens of metres or more. Every reading comes with the phone’s own estimate of its accuracy, and that number matters as much as the position.

• An outdoor depot or car park: accurate, so a small radius works.
• A city office tower or shopping centre: less accurate inside, so allow more room.
• A large site such as a port, campus or construction site: the radius has to cover the whole site, not just the front gate.

Choosing a radius for each site

There’s no single right radius. Start from the site: how big it is, where staff actually start work, and whether they clock in inside a building. A radius that is too tight refuses people standing at the right door. One that is too loose accepts people still in the car down the road.

1. Put the centre where people start work, such as the gatehouse or the staff entrance, not the middle of the block.
2. Start generous, perhaps 150 to 200 metres for a building in the city, and less for an open site.
3. Look at the first two weeks of clock-ins: the distances and the accuracy figures tell you whether to tighten or loosen it.
4. Revisit it when the site changes, such as a new entrance or a move to a different floor.

When it goes wrong

Clocking in from inside a building

Thick walls and basements weaken GPS. Ask staff to clock in as they arrive rather than once they’re deep inside, or widen the radius for that site. Clock-in usually opens a little before the shift starts (30 minutes in TDS Workforce Management), so arriving and clocking in at the door doesn’t cost anyone time.

No signal on site

A clock-in needs a location fix and a data connection at that moment. For remote sites with patchy coverage, agree what staff should do, and let managers correct the hours on the timesheet afterwards. A missing clock-in should be a conversation, not an automatic deduction. Where a site has reliable wifi but phones don’t work well, a kiosk tablet fixed at the site, with a personal PIN for each person, is another way in.

Location turned off or refused

Phones ask for permission before an app can read the location. Explain in advance why the app asks, so staff aren’t surprised the first time. If someone refuses, they can’t clock in from that phone, which is the point of the check.

Faked locations

Apps that fake a phone’s location exist. No check is perfect, so pair the geofence with things that are harder to fake: an optional photo at clock-in, the duty checklist at clock-out, a signature from someone on site, and the client’s own view of who turned up.

What to tell staff

People accept a location check when they understand it. Tell them, in writing and before you start, exactly what is collected and why:

• The position is read when they clock in and out, and at no other time.
• It’s used to confirm they’re at the site, and to settle questions about hours.
• Who can see it: their manager and the admins, not their colleagues.
• How long it’s kept, and how they can see their own records.
• Whether photos are taken, when, and who sees them.

Some places have specific rules. In New South Wales, the Workplace Surveillance Act 2005 requires written notice before tracking surveillance begins, and the ACT has similar rules. In the UK and the EU, location data is personal data under the GDPR, which brings duties of transparency, minimisation and often a data protection impact assessment. Our guide for UK and EU employers goes through them. Wherever you are, check the rules that apply to you.