The number of landlords in the UK increased by 7% to reach 1.75 million in 2013-2014.
Analysis of Her Majesty's Revenue and Customs (HMRC) data carried out by estate agency ludlowthompson show that 1.75 million people declared rental income, compared to 1.63 million in 2012-2013.
The UK's landlords banked a total of £14.2 billion in net income during 2013-14, up from £13.1 billion in the previous year.
These figures are the latest available from HMRC and it is thought that the number of landlords and total income generated will have increased significantly since then.
Last month's introduction of a 3% stamp duty surcharge and the incoming restriction of buy-to-let mortgage interest tax relief for higher rate tax payers has encouraged a period of heightened buy-to-let lending and property purchases.
Earlier this month, board supplier Agency Express reported that new listings 'To Let' increased by over 12% in April, while the number of 'Let' properties increased by almost 9% from the previous month.
The firm said that its figures for the four previous Aprils showed a drop-off in lettings activity when compared to March.