Almost half (44 per cent) of homeowners who share a residence with at least one adult have taken steps towards moving without informing fellow occupants, according to a survey.
Zoopla, which commissioned the research, revealed that actions by these "property traitors" include discreetly looking at listings for sale, assessing current property values, researching new locations, or evaluating personal affordability.
Of those who secretly view housing options, over a third (36 per cent) admitted doing so whilst watching television beside the people they live with.
Nearly a fifth (18 per cent) have searched at work, whereas 12 per cent browse during their daily commute.
Among prospective buyers, more than one in five (21 per cent) said they would wait until fully certain of moving before revealing their plans to cohabitants.
Richard Donnell, executive director at Zoopla, said: “Anyone thinking about buying a home today has more to weigh up, with higher mortgage rates limiting buying power but more homes for sale, giving buyers greater choice and more room to negotiate.
“Doing your homework early is important.
“That means understanding what you can afford, looking at how far your budget will stretch in different areas and, for existing homeowners, knowing what your current home is worth and how much equity you have to put towards your next purchase.”
Opinium surveyed 2,000 people across the UK who live with another adult in September.
It comes after a new study found affordability across the UK has reached its most accessible level in more than a decade, with the average home now valued at 7.3 times average annual earnings.
New analysis by Lloyds evaluated data from its own house price index alongside official statistics from the Office for National Statistics (ONS), comparing figures for the second quarter of 2026 against corresponding periods in prior years.
An assessment across all quarters confirmed that the ratio has not fallen below 7.3 for 11 years.
This closing of the affordability gap over the past year has been driven by wage growth outstripping the rate of property price increases.
For individuals attempting to purchase their first home, the typical property now costs 5.9 times average earnings, placing it just under six times income.
However, Northern Ireland deviated from the wider UK trend over the past 12 months. There, house prices climbed faster than wages, driving the average price-to-earnings ratio up to 6.0 from 5.8.
The most marked improvements in affordability were generally seen in regions where housing costs remain highest relative to pay.
London recorded a fall from 10.9 to 10.3 times earnings, while the South East dropped from 9.7 to 9.1. In Eastern England, the ratio fell from 8.7 to 8.2, while the South West saw a reduction from 8.2 to 7.7.
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