Whether landlord insurance is mandatory is a question that mixes three different kinds of obligation, and separating them gives a clear answer. One cover is compulsory by statute. Several are compulsory by contract. The rest are decisions. Nothing about a let property makes landlord insurance itself a legal requirement in the United Kingdom.
Compulsory by statute: one item only
Employers liability insurance, from the moment anybody works for you rather than for themselves, to a statutory minimum limit, with a penalty charged for every day you trade without it. A landlord with a cleaner, a caretaker or a gardener on their instruction needs it. A landlord using genuinely self employed contractors who carry their own does not.
Compulsory by contract: the mortgage and the lease
A buy to let mortgage will require the building insured for full reinstatement against listed perils, continuously, with the lender's interest noted. A lease on a flat will oblige somebody, usually the freeholder, to insure the structure. Neither is a statutory duty and both are enforceable, which for practical purposes makes them compulsory.
Not compulsory but hard to justify declining
Property owners liability, because the exposure exists whether or not it is insured and the claim is priced on an injury rather than on the building. A landlord who declines it is self insuring an open ended liability to save a small part of a premium, which is a decision very few would make if it were put to them in those words.
What is genuinely a choice
Loss of rent, landlord contents, accidental and malicious damage, rent guarantee, legal expenses and home emergency. Each of these is a judgement about your own circumstances, and a landlord with no mortgage and reserves can reasonably decline several of them.
Questions people ask about is landlord insurance mandatory
Is landlord insurance required by law in the UK?
No. Only employers liability is compulsory by statute, and only if you employ anybody. Everything else is required by a mortgage, a lease or judgement.
Will my lender insist on it?
A buy to let lender will require buildings cover on stated terms as a condition of the loan, and can insure the property itself and charge you if it lapses.
What happens if I let without any insurance?
It is lawful unless you employ somebody, and it breaches almost every buy to let mortgage. The building and the liability are then uninsured.
Is employers liability really needed for a cleaner?
If they work for you rather than for themselves, yes, and the penalty is charged for each day without it. The test is the working relationship.