The data, compiled following Freedom of Information (FoI) requests, indicates that Northumbria spent nearly £660,000 for criminal intelligence between 2014-19.
The £659,823 sum is the fifth highest out of the 27 forces which responded with figures.
It is also more than treble the payments made by its smaller neighbour, Durham Constabulary, over the same period.
Northumbria’s expenditure, however, has gradually fallen since 2014 from a high of £185,550 in 2014-15 to a low of £102,810 in 2018-19.
A spokesperson for the force insisted that money paid to informants was “closely scrutinised”.
They added: “The use of informants is just one tactic adopted by police forces across the country to help protect communities.
“The intelligence provided helps prevent and solve the most serious of crimes and bring offenders to justice.
“This is a well-established and highly regulated tactic with the money paid to informants closely scrutinised.”
Durham Constabulary, which have still to comment, spent £193,193 over the 2014-19 period.
Their figures have also fallen in that time from a high of £43,667 in 2014-15 to £29,287 in 2018-19.
Cleveland Police, which spent £77,412 over the same period, have seen payments drop in from £17,000 in 2014-15 to £14,845 in the last financial year.
The figures show that the Metropolitan Police were the highest spenders with informants receiving £4,363,226 over the past five years.
North Wales Police spent the lowest amount, just under £55,000, during the same period.
Eighteen forces failed to provide details of their expenditure in response to the FoI request from the University of Portsmouth journalism department.
A spokesperson from Taxpayers’ Alliance said: “It is critical that there is transparency in how taxpayers’ money is spent, even in the murky world of crime-fighting.
“All bodies, including the police, ought to be aware of the public interest in knowing where their cash is being spent, especially given that taxpayers are being asked to pay record amounts this year.”
The overall 2014-19 figure from the forces who did respond was £13.6 million.