Types of numbers you need to know and where to find them

When registering your test, you will be asked for certain numbers, codes or an ID. The table below gives you examples of what these numbers should look like and where you can find them.

Type of Number



Order ID


This typically consists of two letters (usually your initials) followed by some numbers and can be found on your order confirmation email or on your Chronomics dashboard.

Kit ID


4 letters followed by 4 digits.

This can be found on the outside of the box the test is delivered in, or on a label stuck on the plastic bag that has the test inside. This number is unique to each test.

For U.S customers - Your Kit ID will be printed on a leaflet that will be inside your testing kit.


NH054111111 or CHR00001234/

For PCR tests, this can be found on the test tube or for rapid antigen tests, on the plastic cassette.

This usually starts with a  5, NH0, CHR0 or BHA.

For U.S customers - You won't have a barcode on your test cassette as barcodes aren't required for you to register your test. 

Passenger Locator Booking Reference Number (PLF Number)

CHRON0123456 or CHROM0123456

This is the number you need to put into the UK Government Passenger Locator Form.

This can be found in your original order confirmation email or on your dashboard. 

Please note: You'll only have a passenger locator form reference number if you've purchased a Day 2 test. PLF's are not given with any other test type. 

PLEASE NOTE: If you’re having trouble registering your test due to Kit ID/Barcode issues, please ensure you're using Google Chrome to register your kit. If you need to contact us for help, please provide images of your barcode/Kit ID where possible.