This depends on the type of airport lounge and the credit card. For example, with the HSBC Visa Infinite Credit Card, you are required to present your primary or supplementary card and boarding pass to the lounge operator.Some credit cards partner with airport lounge programmes, which each run their own chain of lounges. Common ones are Priority Pass, Plaza Premium, SATS lounge and Dragon Pass. For most of these lounges, you will be invited to join the particular airport lounge programme a few days or weeks after you sign up for a participating credit card.It might take a few weeks to process your membership, so don’t apply for a credit card the night before you fly off. Membership is usually on an annual basis. In other cases, such as the SIA KrisFlyer Ascend, you will receive airport lounge vouchers which you present at the front desk of the lounge before entry. You might also be asked to present your credit card and boarding pass.Remember that each bank will issue you a separate Priority Pass, and your free visits are tied to an individual card – so don’t mix them up! Label your cards carefully and note down how many visits you have used on each.Also, check if your free visit entitlement is renewed each membership year (i.e. the anniversary on which your lounge pass was issued) or each calendar year (i.e. 1 January 2022 – 31 December 2022). The majority of banks award free lounge visits by membership year, although Citibank’s PremierMiles cards award free visits based on the calendar year.