Tenants saw rents increase for the third consecutive month in February.
The latest index of private housing rental prices from the ONS shows rents rose by 1.1% annually in the UK last month, up from 1% in January.
The trend comes after rental growth remained flat for much of 2018, according to ONS data.
Northern Ireland had the highest rate of growth among the UK regions at 2%.
The slowest growth was in Scotland, where rents increased by just 0.7% in the 12 months to January, while prices were up 1.1% in both England and Wales.
When London – where rents rose 0.2% – is excluded from England, rents increased by 1.6%.
Commenting on the figures, Tom Mundy, chief operating officer at Goodlord, said: “The trend of rising rents that we’ve seen since January 2015 shows no signs of abating, despite prices in the London rental market only rising 0.2% in the 12 months to February 2019.
“Whilst this is good news for landlords, wage stagnation means these rent rises are set to hit generation rent extremely hard.
“Despite record levels of employment, more and more young people are on course to become life-long renters, meaning every month we see rents rise is another month where a whole generation will feel the impact on their bank balance and their standard of living.
“To justify these increases, I think now, more than ever, landlords and the wider market have an increasing responsibility to ensure the experience of renting is positive and enjoyable for everyone involved.”