First-time buyers borrowed a total of £5.9 billion in June - marking a 26% surge on May amid a "busy month" for the mortgage market - according to banks and building societies.
Trade association UK Finance, which released the figures, said first-time buyer borrowing was also up by 9% compared with June 2016.
Despite the upswing in activity in June, UK Finance said it did not believe overall performance levels would be sustained in the second half of 2017, amid signs that the market is now softening.
People taking their first step on the property ladder took out bigger loans in June compared with the previous month, at £139,000 on average in June compared with £137,000 typically in May, its figures showed.
Separate figures released jointly by the Office for National Statistics (ONS), Land Registry and other bodies showed that, across Britain, the average first-time buyer faced paying 4.9% more in June for a home than they did a year earlier, with the typical price paid at £188,947.
UK Finance's figures also showed that home-movers borrowed £7.8 billion in June, which was also by up 26% on May, as well as an increase of 15% year on year.
Meanwhile, buy-to-let lending totalled £3 billion, up 3% on May and a 3% increase compared with a year earlier.
And home owners took out £6 billion-worth of re-mortgage loans, up 5% by value on May and 7% compared with June 2016.
Paul Smee, head of mortgages at UK Finance, said: "June's figures show a busy month in the mortgage market, with home-movers having their highest monthly activity levels for over a year and an especially high number of loans for first-time buyers.
"Buy-to-let activity remains subdued compared to its 2015 peak but consistent month to month since stamp duty changes in April 2016.
"But there are also signs of a softening market and we are not anticipating that this performance will be sustained in the second half of 2017.
"A slightly lopsided market could well show some growth in house purchase lending but alongside reduced re-mortgage and buy-to-let activity."