Under the Equality Act 2010, it is unlawful to discriminate on the basis of 'protected characteristics' such as race, gender, sexual orientation, religious belief or disability, including when deciding whether to rent a property to a prospective tenant.
It is worth noting that this includes not only direct discrimination (e.g. advertising for males or females only) but also what is known as indirect discrimination, i.e. applying criteria which disproportionately affect particular groups; for example, a blanket policy of not accepting 'DSS' tenants is likely to be unlawful because it adversely affects women and disabled people (unless the landlord can show that their policy is a proportionate means of achieving a legitimate aim).
There are partial exceptions for people who are renting out parts of properties that they (or a close relative) will be occupying themselves, and sharing particular parts of that accommodation with their tenant - for example, a landlord who takes in a lodger who will be able to use the kitchen. Landlords in this position are still not permitted to discriminate on the basis of race (including nationality and origin as well as skin colour), but may state a preference otherwise, such as stating a preference for male or female tenants.
It is important to note that this exception is only available to those who meet the particular criteria outlined in the Equality Act; landlords who will not be living at the property themselves (or renting to a close relative) are not permitted to state such preferences.
OpenRent's support team will always do their best to enable landlords to advertise with as much freedom as the law allows, but please note that our team may sometimes need to amend adverts if there appears to be a risk of the advert containing unlawful content. This is for the protection and benefit of all our users.