Hi there,
In order to share a personal liability or household insurance policy you will normally need to live in a registered partnership or marriage with your co-policyholder. If this is the case, then getting a single policy for both you and your partner instead of keeping two separate policies means you only need to pay one premium instead of two.
While most insurers require that you complete your insurance term before terminating your policy, some insurers allow you to add a person to your policy before your term ends. Each insurance company has its own set of rules governing early terminations. Just contact your insurance provider to find out whether you they allow early terminations for policyholders who wan to join their partner's insurance policy.
Best regards from Moneyguru
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