It appears you may be a Partnership by 'de-facto'
The Partnership Act 1890 Act describes a partnership as ….
'the relation which subsists between persons carrying on a business in common with a view of profit.’
Given that the existence of a Partnership is a matter of fact, your accountants should have advised you to register the Partnership with HMRC several years ago and submitted SA800 Partnership returns since then. However, given that you would have paid no more or less tax as a result of this, HMRC take a pragmatic view on oversights of this nature. The reason for this is that property investment was not regarded as a business activity by HMRC until the lost their case against Elizabeth Moyne Ramsay in the Upper Tier Tax tribunal in 2013. That case wasn’t widely publicised until much more recently, so in fairness to your accountants, that may well be why they wouldn’t have thought to register your Partnership.
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