Police spending on some goods and services has gone up despite a drive to bear down on procurement costs, according to new figures.
Government statistics reveal increases in the prices paid for credit reports, belts, batons and handcuffs.
They also lay bare large differences in amounts spent on the same equipment, such as bikes and helmets.
The findings were detailed in the latest analysis in a series launched by the Home Office in 2015 to ensure forces in England and Wales were achieving value for money.
We will continue to work with the police to make sure that the taxpayer is getting value for moneyNick Hurd, Police Minister
Currently they spend around £2.5 billion on goods, services and third parties, equivalent to nearly a quarter of the total £11 billion budget for 2017/18.
The “basket of goods” exercise draws together data on prices paid for 49 items across 10 categories.
Officials collate the most recently available purchase information for goods such as police helmets, shirts, and vehicles, as well as services such as gas and interpreters.
Publishing the latest findings, the Home Office said forces were saving up to 63% per item through buying collectively and purchasing in bulk, which had contributed to savings of £273 million since 2015.
But the department said the latest exercise revealed areas which had worsened since the last datasets were released in August 2016.
These included credit reports, for which the median spend across forces went up by 262%, as well as belts (21%), batons (11%), and handcuffs (6%).
The figures also pointed to discrepancies in spending on some goods and services, including police push bikes, with costs ranging from £279 to £539 per bike. Police motorcycle helmets were bought for between £291 and £656.
Police Minister Nick Hurd said: “This year, taxpayers will be investing an additional £460 million in our police system. They do not expect the police to waste their money through inefficient procurement.
“I congratulate the police on impressive progress in recent years to squeeze out inefficiency. However these numbers show that the work is not complete.
“We will continue to work with the police to make sure that the taxpayer is getting value for money.”
The assessment said most of the savings apparent in the latest figures resulted from a programme to identify opportunities for collaboration.
For example, forces in Bedfordshire, Hertfordshire and Cambridgeshire bought uniforms together to halve the cost of their fleeces from £32.95 to £15.95.
Other “highlights” flagged up by the Home Office included a 63% drop in the cost of jackets acquired by the Metropolitan Police and 60% reductions in the costs of utility belts (Norfolk and Suffolk) and shirts (Lincolnshire).
National policing lead for finance Dave Thompson said: “We have already delivered substantial procurement savings and have identified another £100 million of savings over the next three years.
“While there are considerable challenges to overcome in more complex areas of procurement, we continue to work hard to find further efficiencies and provide the best possible service to the public.”