The CI Co-Op is the new provide of fuel for a number of States departments.
The new deal was agreed in December 2023.
The States say it will 'offer better value for money and more flexible locations for filling up.'
Currently it applies to vehicles run by Guernsey Water, Health and Social Care and Education's Pupil Transport Service.
Previously, these departments had used a locally run garage.
It's unclear whether the agreement covers States Works, which operates a large and diverse fleet.
Possible job cuts at RBSI in Guernsey and Jersey
The bank says it is simplifying operations as finance becomes increasingly digital.
Guernsey students beat England's A level pass rate
Guernsey students performed slightly better in A-Levels than their English peers.
Guernsey community unites out west for solar eclipse
Thousands of islanders basked in the August heat to watch the once-in-a-generation partial solar eclipse.
19 months of traffic lights on busy Guernsey road
The Charroterie will have temporary lights from the end of August till March 2027 to enable 70 new flats to be built.
New Dean of Guernsey has Alderney connections
Matthew Trick will be installed as the Dean of Guernsey in late September having recently been Alderney's locum priest.
Guernsey's youngsters concerned by the high cost of living
The latest Public Health report shows a significant number of 16-24 year olds are put off staying on the island because of cost pressures.
A solar eclipse and meteor shower over Guernsey tonight
Guernsey's west coast will experience 94.5% totality as the moon obscures the sun.
Average Guernsey home selling for more than £600,000
Rent prices slow but are still up 34% over five years.
