Do I need my own payment gateway to take card payments on my website, or does one come with the portal?

Yes, in most cases you will need your own merchant account and payment gateway, and the portal is then connected to it so that the money from every booking lands in your own bank account. Most travel businesses prefer it this way, because you stay in control of your own funds and you deal directly with your own bank on charges, settlement times and chargebacks rather than waiting for someone else to pass the money on.

Which gateways can be connected depends on your country and on what your plan covers. The gateways commonly used by travel companies can normally be integrated, but that is not a promise for every provider in every market, so it is worth naming the gateway you have in mind at the start rather than after the site is built. Some gateways also ask for extra approval before they will accept travel transactions, because travel is treated as a higher risk trade, and that approval sits between you and the gateway.

If you do not have a gateway yet, you do not have to wait to go live. Bookings can be set up so the customer books online and your team collects payment offline by bank transfer, by card machine or in the office, and confirms once the money is in. You can switch the online card option on later without rebuilding anything.

Before you go further, check whether your bank or gateway account is already approved for travel and which currencies it settles in, then share those details so the connection can be set up and tested with one small live payment before you open the site to customers.