How to calculate mileage between two postcodes for UK freight planning

Knowing how to calculate mileage between two postcodes sounds basic, but it is one of the first checks behind a sensible freight rate. Pop two postcodes into the CTS mileage calculator and you get road miles, an HGV time estimate and an indicative diesel cost in seconds, no account or sign up. That matters when a quote lands late, a regular lane changes, or a via point turns a straightforward run into something different. I treat any calculator as a planning aid, not a substitute for knowing the job, but good mileage, time and fuel assumptions stop guesswork.

What the CTS mileage calculator gives transport buyers

A useful result needs more than a line drawn between two pins. CTS accepts a start postcode, a destination postcode and an optional via postcode. Full postcodes such as LS10 1AB can be used, or outward only codes such as LS10 if that is all you have at the quoting stage. The tool returns road miles and kilometres, an estimated HGV journey time, an indicative diesel cost, and a live route map, with a PDF you can drop into a job file.

That combination suits buyers checking a rate, operators pricing a backload, and planners comparing options on a lane. It is also handy for longer term thinking. If you are weighing up a regular movement or looking at contract haulage, consistent mileage and fuel assumptions keep discussions grounded. You can see how a via point shifts distance and time, and whether a quoted figure looks realistic before you pick up the phone.

What sits behind the mileage and cost figures

The calculation starts with postcode geocoding using postcodes.io, built on Ordnance Survey and Office for National Statistics open data. When you enter an outward only code, the tool uses the district centroid, so results are approximate at postcode area level. Road distance and drive time come from the OSRM routing engine on OpenStreetMap data. OSRM models a car, so the calculator applies a 0.85 speed factor to reflect HGV operation. In practice that means an HGV is assumed to average 85 per cent of car speed, which makes the journey about 18 per cent longer. The time shown is free flow driving only, with no allowance for rest breaks, loading, congestion or drivers’ hours limits.

Fuel is calculated in miles per imperial gallon, with 1 gallon equal to 4.546 litres. The default is 9.5 mpg for a typical 44 tonne articulated lorry and 28 mpg for a 3.5 tonne diesel van, multiplied by an editable diesel price. The starting price comes from the official UK government DESNZ weekly road fuel prices statistics on gov.uk, refreshed weekly, 164.5p per litre at 13 July 2026. If the routing engine cannot be reached, the tool falls back to a straight line distance multiplied by 1.25 to approximate road winding, and it is labelled as an estimate so you know to treat it with care.

Put the route into the calculator

1. Enter the start postcode and the destination postcode.
2. Add a via postcode if the load must pass through a specific point.
3. Pick the vehicle type and adjust the diesel price if you need to mirror your own assumptions.
4. Click Calculate route.
5. Review the figures, check the map and download the PDF for your file.

Use full postcodes where you can. You will get a tighter route and a better planning estimate for a rate discussion, but always sense check for HGV suitability. Outward only codes are handy early on, but they sit on a district centroid, so treat them as a planning steer rather than a final number. If a job has a fixed delivery window or awkward access, put a via point on the roads you expect the driver to take. It helps reduce the risk of pricing a route that looks fine on paper but may not suit a 44 tonne artic.

Turn the result into a buying decision

Now use the figures rather than re-reading the maths. The estimated HGV time is free flow driving only, so add your own allowance for breaks, loading and congestion before you promise a slot. If the number lands close to a drivers' hours limit or a tight delivery window, that is your cue to build in slack instead of quoting a best case that falls over on the day.

Treat the diesel cost as a like for like baseline, not a fixed spend: drop in your own bunker rate and it becomes a fair way to weigh one lane, vehicle or routing option against another. If the map is flagged as an estimate because the routing engine was unreachable, take the distance as indicative and recheck it before you commit. Between the miles, the time and the fuel, you have enough to sense check a quote and to brief an operator without hand waving.

Run your lanes through the mileage calculator and keep the PDF with the job. If you want firm prices from vetted operators, send the same detail through request quotes and compare like with like.

Frequently asked questions

How do I calculate mileage between two postcodes for a lorry in the UK

Enter the start and destination postcodes in the CTS mileage calculator and click Calculate route. It returns road miles, an HGV time estimate and an indicative diesel cost with a route map.

Are the journey times from a postcode mileage calculator accurate for HGVs

The time is based on a car routing model adjusted so an HGV averages 85 percent of car speed, making the trip about 18 percent longer. It is free flow driving only and excludes breaks, loading, congestion and drivers hours limits.

Why do results change when I use only part of a postcode

Outward only postcodes use a district centroid for geocoding, so the start or end point is approximate. Full postcodes give more precise routing and more reliable mileage and cost figures.