Departments increased their spending on temporary staff to £7.38bn in 2022-23, according to just-published data provided to MPs by the Cabinet Office.
The contingent-labour figure represents a 4.5% increase on the previous year's £7.06bn, but also comes against the backdrop of a declining bill for consultants.
Even so, civil service full-time staff numbers have continued to increase over the period. According to the annual Civil Service Statistics, there were 487,665 full-time equivalent officials at 31 March 2023, up from 478,090 at the end of March 2022.
The increased spending on temporary staff is detailed in a letter to members of parliament's Public Accounts Committee from Cabinet Office permanent secretary Sir Alex Chisholm and government chief people officer Fiona Ryland. It was sent as a follow-up to an evidence session that took place last month.
Earlier this week, Chisholm told the Public Administration and Constitutional Affairs Committee that government expenditure on consultants had fallen from £1.6bn in 2021-22 to £1.19bn in 2022-23 – a decrease of around £400m. The temporary-staff costs, meanwhile represent an increase of £320m.
The letter from Chisholm and Ryland, which was dated February 16 but only published on Monday, said the Cabinet Office's spending on temporary staff actually increaed by almost 20% between 2021-22 and 2022-23.
It reports that the department spent £59.1m on temp staff in the last financial year, up from £49.3m in 2021-22.
Think tank the Institute for Government's most recent Whitehall Monitor report flagged departments' use of temporary staff as a cause for concern. It said the Department of Health and Social Care, the Ministry of Defence, the Home Office and the Foreign, Commonwealth and Development Office had all chalked up escalating spend in recent years.
According to the Home Office's annual report and accounts for 2022-23, the core department spent £244.1m on temporary staff, up from £133.6m the previous year.
FCDO's latest annual report and accounts shows £49.1m of spending on temporary staff in 2022-23, up from £39.6m the previous year. The department's arm's-length bodies added a further £328,703 of spending on temporary staff in 2022-23, up from £176,381 the year before.
The MoD and its executive non-departmental public bodies spent £375.9m on temporary staff in 2022-23, down from £483.4m the previous year.
DHSC's most recent annual report and accounts states that the core department spent £416.4m on temporary staff in 2021-22, but that the figure dropped to £23.1m in 2022-23, primarily because of the transfer of the UK Test and Trace programme to the UK Health Security Agency.
The IfG's Whitehall Monitor report noted that pressures related to Covid-19 had driven a 15-fold increase in DHSC's contingent labour costs between 2018-19 and 2021-22.
A Cabinet Office spokesperson said the government had taken steps to reduce consultancy and contingent labour spending, with greater transparency in monthly workforce-management reporting.
"Stringent controls are in place to ensure consultancy and contingent labour spend is managed appropriately and represents good value for money for the taxpayer," they said.