The conservation charity's income in the year to February was £436m but it also reported a shortfall in its pension scheme and investment losses
The trust also saw its income from membership – its single largest source of funding – increase to £129.6m from £124.3m in the previous year.
But the charity spent £450m in the year, leading to an operating loss of £14m. It recorded a further loss of more than £50m because of a shortfall in its pension scheme, as well as investment losses, leading to total loss on the year of £70m.
The charity retains reserves of £126m and has investment assets of £921m.
In its annual report, the National Trust said it had been surprised by the success it had had in the year in increasing visitor numbers.
It said it had reached four million members for the first time, had more than 19 million visitors to its attractions and attracted 67,000 volunteers.