Can my customers add travel insurance when they book a trip on my portal?

Yes, in many cases they can, but it is not something that is simply there from day one. Insurance is sold by an insurance company, so it has to be connected to your portal in the same way a flight or hotel supplier is connected. Once that is done, the cover appears as an extra step during booking, usually just before payment, and the customer chooses whether to take it or skip it.

What the customer is offered depends entirely on the insurer you work with. Some give a single simple cover per traveller, others price it by age, trip length or destination, and some only cover residents of one country. The portal shows what the insurer sends back, so it cannot offer a cover the insurer does not sell for that trip. The policy document and any claim your customer later makes are handled by the insurer, not by your agency and not by the portal.

Whether this option is included for you depends on your plan and on whether you already have an arrangement with an insurance company. If you do not have one, you would need to set that up first, and the earnings you make on each policy are agreed between you and the insurer.

If selling insurance matters to your business, ask your account manager whether your plan supports it and have your insurer's contact details ready when you do, because the connection cannot be started without them.