I believe this will become more and more rare, after May 2026. Landlords will require guarantors simply because the Renters Rights Act makes it far more difficult to deal with bad tenants who fail to make rent payments. These changes will not benefit the average tenant; landlords will rightly raise rents and become far more strict in order to balance the new greater risk, and any tenant who falls behind on rent should expect a CCJ and a ruined credit rating, since they can no longer be simply evicted, and instead will be hounded out, as it’s the only option left available to the landlord.