Buy-to-let landlords have been dealt a new blow in the Budget after the Chancellor abandoned plans to exempt ‘significant investors’ from the extra 3 per cent stamp duty charges and snubbed them in a capital gains tax cut.From April, anyone purchasing an additional property will have to pay an extra 3 per cent stamp duty. But George Osborne used his Budget today to reject initial proposals that would have meant ‘significant investors’ – both companies and individuals – buying more than 15 properties were exempt.This has removed the loophole that would have allowed buy-to-let investors to club together and buy multiple properties through a company to avoid the extra tax.And buy-to-let and second homeowners were also deliberately excluded from a big capital gains tax cut from 28 per cent to 20 per cent.