Some 74 million passengers travelled through UK airports in 2020, analysis of Civil Aviation Authority data by the PA news agency revealed.
This is less than a quarter of the 297 million recorded during the previous 12 months.
The Airport Operators Association (AOA) said the statistics demonstrate the “devastating impact” of the virus on aviation.
Cardiff Airport suffered the largest decline at 86.7%, followed by Glasgow Prestwick (85.8%) and Exeter (85.5%).
Other airports with the biggest decreases in passengers include Southampton (83.4%), London City (82.3%) and Leeds Bradford (81.2%).
The UK’s largest airport, Heathrow, recorded a 72.7% reduction, from 80.9 million passengers in 2019 to 22.1 million last year.
The figures include all passengers who travelled through British airports excluding the Channel Islands or Isle of Man.
Demand for air travel collapsed in March as the UK went into lockdown due to the coronavirus outbreak.
A partial recovery had occurred by late summer and early autumn, but passenger numbers plummeted again in November after many restrictions were reimposed in the face of a second wave of the virus.
AOA chief executive Karen Dee said: “These figures lay bare the devastating impact Covid-19 has had on UK airports.
“With passengers down nearly 90% between April and December 2020, airports’ economic output was decimated and significant numbers of jobs were lost.”
With travellers from every major viable tourist destination currently required to go into quarantine when they return to the UK, Ms Dee warned that the Government’s “overly cautious” approach to reopening travel means this summer will be “as bad, if not worse, than 2020”.
She went on: “This leaves UK airports trailing behind international competitors in the EU and US, who not only received significantly more financial support from their governments but are also now able to restart travel over the summer.
“To ensure there are viable airports to support the economy and Government agendas like global Britain and levelling up, the Government now faces the choice of either meaningfully restarting aviation or setting out a comprehensive package of support to compensate airports for the impact of Government policy.”