A Basic Guide to Supplementary Credit Cards

Supplementary credit cards are a great way to maximise your credit card rewards, or even extend credit to your loved ones. However, as with regular credit cards, there are some risks that come with it. In our guide, we discusses all the ins and outs of supplementary cards.

ValueChampion Editorial Team

by ValueChampion Editorial Team on Mar 12, 2024

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Supplementary credit cards can make a great addition to a principal credit card account. However, there are quite a few risks that come along with the associated benefits. The guide below discusses how and when to effectively use supplementary credit cards.

Table of Contents:

What is a Supplementary Credit Card?

If you currently have your own credit card, chances are you’re eligible to apply for an accompanying supplementary credit card. These cards are usually reserved for a family member like a spouse or child. Supplementary cards also typically share the same rewards structure as the principal card, allowing cardholders to boost overall earnings. In addition, supplementary cardholders can enjoy special perks and privileges associated with the principal card.

You can apply for most supplementary cards online, or by simply mailing in an application form. Primary cardholders may even earn bonus miles or extra cashback for each successful application. Finally, most–but not all–supplementary credit cards are either free or have a very low annual fee, making them an attractive addition to an account.

Examples of Credit Cards with Free Supplementary Cards

Credit CardPrinciple Annual FeeSupplementary Annual Fee
HSBC Revolution Credit CardS$0.00S$0.00
Citi PremierMiles CardS$196.20S$0.00
UOB Lady’s CardS$196.20S$0.00
Standard Chartered Simply Cash Credit CardS$196.20S$0.00

Related: Best Cashback Credit Cards in Singapore 2024

How Does a Supplementary Card Actually Work?

Supplementary credit cards are fairly easy to use, but do not work in exactly the same way as a principal card. As mentioned, most supplementary cards share the same rewards structure as the primary card; if the primary offers 5% rebate on dining, so too does the supplementary card. However, transactions on a supplementary credit card are consolidated and reflected in the primary cardholder’s statement. Therein, the primary cardholder bears responsibility for all posted purchases and fees.

Rewards earned are also processed differently. The 5% rebate earned from a supplementary cardholder’s dining spend, for example, is credited back to the primary cardholder’s account. In the case of cashback, the cumulative earnings are usually applied to offset the next month’s consolidated bill. With travel cards, however, all miles accrued are directed to the primary cardholder’s account, and only he or she can redeem them. The distribution of rewards is a topic worth discussing before agreeing to share a supplementary card with a family member.

Related: 4 Key Questions To Ask Yourself Before Signing Up For A Credit Card

Sharing a Supplementary Card with a Spouse or Child

As mentioned, supplementary credit cards are most typically used by a spouse or child. For a spouse, a supplementary card offers an opportunity to boost rewards overall as a couple, while also minimising annual fees. This is especially true for expensive cards, where total fees average out to a more moderate sum between two people.

Supplementary cardholders can also enjoy added perks associated with the primary account, unless otherwise stated. It’s still important to review the principal card’s terms and conditions as benefits like free airport lounge visits may not carry over in an equivalent way.

Selection of Luxury Supplementary Credit Cards

Credit CardPrincipal Annual FeeSupp. Card Annual Fee (1st Card)Ave. Cost Per PersonShared Perks
UOB PRIV Miles Amex CardS$261.60S$0.00S$130.80Free limo transfers
CIMB World MasterCard Credit CardS$0.00S$0.00S$0.00Preferential rates for golf green fees, airport lounges and travel and spa offerings in airports
* Rates, fees and perks as of March 2024. Average cost assumes 2 people, principal and supplementary cardholder

While sharing a supplementary card with a spouse is a great way to quickly earn rewards without extra fees or maintenance, sharing such a card with a child deals more with supporting their development. Supplementary cardholders typically must be at least 16 to 18 years old, and their spend is reported in the principal cardholder’s monthly statement.

Sometimes, principal cardholders can set a separate credit limit for supplementary cardholders, which minimises overall risk. However, it’s essential to keep a close eye on monthly statements and remain engaged with a child’s spending behaviour. Ultimately, the principal cardholder is accountable for all transactions made on the account.

Related: Should You Get Your University-Bound Child a Supplementary Credit Card?

Benefits and Drawbacks of a Supplementary Card

Overall, supplementary credit cards come with both benefits and drawbacks.

Spend on supplementary card counts towards primary cardholder’s min spendPrincipal cardholder responsible for paying off supplementary card charges
Double spending powers boosts overall earningsShared card limit means primary cardholder spending limit is decreased
Lower or no annual fee for supplementary cardsPrincipal cardholder’s credit score could be adversely affected

Overall, the best scenario for using a supplementary card is when the primary card is expensive and does not have a rewards cap (typically, miles-earning and unlimited cashback cards). It’s important to only share supplementary cards with trusted individuals who have shown themselves to be financially responsible.

If you are in the market for a new credit card, check out our collection of credit card articles to learn more about the product as well as our round up of the best credit cards in Singapore to find the right credit card for you.

Cover Image: Pexels


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