The easy answer would be "always". That's because trip cancellation insurance is designed to be there when you least expect to use it. Here's what we mean: this insurance is designed to provide you with security for the costs you incur to book a hotel and/or airfare if your trip doesn't go ahead for reasons beyond your control (e.g. unforeseen health, work and property events that may prevent travel) and is different from stndard travel insurance.
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