Buy-to-let lending is down 47% on levels before the introduction of the 3% Stamp Duty surcharge levied on the purchase of additional properties.
It is also down 64% compared with the pre-2007/2008 housing market crash.
In a new report on the residential housing market, Cushman & Wakefield say that with further phasing in of the reduction in income tax relief will ensure that lending activity stays muted.
The consultancy also notes that some landlords are selling off properties, and that there are only limited numbers of new investors entering the market.
Nevertheless, Cushman & Wakefield think that housing stock in the English private rented sector will contract by no more than 3% over the next two years.
Its report also shows a mismatch between supply and demand, particularly with the most expensive and cheapest properties.
In March, 6.1% of properties listed on Rightmove were at over £1m. However, just 2.7% of completed sales that month were for over 2.7%.
The opposite was true in the sub-£200,000 market, which accounted for 45% of all sales but just 30% of listings.