Wednesday marks one year to the day since a devastating hailstorm swept through the nation's capital, carving out a trail of destruction and sending Canberrans ducking for cover.

While an exact cost of the damage from the storm to the ACT alone hasn't been able to be calculated, the damage bill from the entire storm system - which first went through regional Victoria, on to the ACT and into parts of Sydney - has been estimated to be more than $1.65 billion.

According to figures from the Insurance Council of Australia, almost 131,000 claims were made for damage stemming from the hailstorm, with insurance claims for cars making up more than half of that figure.

A further 39,296 claims were made for residential buildings and more than 10,500 for contents insurance.

Insurance claims from the ACT accounted for 57 per cent of all claims made from the storm, making up 74,660 claims. The council said Victoria made up 30 per cent of insurance claims while the remaining 13 per cent came from NSW.

The extent of the hail damage was so large and the backlog so great that building repair companies who were contracted by insurers moved to set up permanent offices in Canberra for the first time to deal with the influx of repair jobs, many still being undertaken as of January 2021.

One such company, Bay Building Group, set up headquarters in the ACT to deal with an initial load of 300 repair jobs for the hail, some totalling more than $100,000 in damage.

With hailstones the size of golf balls, some measuring more than four centimetres, it was the worst hailstorm to hit an urban area in Australia since the 1999 Sydney hailstorm.

The ACT State Emergency Service responded to more than 2000 requests for help in the wake of the storm last January.

"This response was supported by the other services of the ACT Emergency Services Agency and our cross-border colleagues from the NSW State Emergency Service," an ESA spokeswoman said.

With car damage accounting for the most claims made to insurers about the storm across the three jurisdictions, it was little surprise that tens of thousands of vehicles in the ACT were affected by dented bonnets and smashed windscreens.

ACT government figures showed more than 44,500 ACT-registered vehicles were damaged during last January's storm. Of those, more than 7000 vehicles were not insured.

The Canberra hailstorm also led to devastation for Canberra's wildlife. The storm resulted in the deaths of more than 600 flying foxes in Commonwealth Park, according to the National Capital Authority.

At the height of the storm, winds in the ACT reached more than 116km/h.

Meteorologist at the Bureau of Meteorology Hugh McDowell said the storm was caused by a super cell with wide areas of low pressure resulting in multiple thunderstorms.

"It was quite unusual for hail to have impacted Canberra like it did, usually the geography of Canberra with the mountains around it protects it from hail," he said.