A pilot payment-by-results project hopes to collect Enfield LBC's historic council tax debt previously written off as uncollectible.
The council has signed a new agreement with IT firm Agilisys, which will earn a proportion of income collected but receive no fees if it fails.
Cabinet member for finance, Cllr Andrew Stafford, said: ‘Enfield LBC is proud of the fact that we are one of the best performing boroughs when it comes to council tax collection and that 98% of all debt is collected successfully.