It's a waste to only rely on a regular savings account at the bank. Recently, more options for credit card installment savings have become available, so many people might be unsure which to choose. Once you set up a credit card installment, it automatically deducts payments, so you can earn points passively, which is the best part. However, there can be significant differences in cashback rates and ease of using points.

If you're starting with small amounts of less than 50k yen per month, d Card is definitely the top choice. It has no annual fee and offers a high cashback rate of 1.10%, and d Points can be used at many locations. Combining it with Monex Securities makes it convenient to choose from over 200 investment trusts. Just be careful, as the cashback rate drops if you invest more than 50k yen.

For those wanting to invest more than 50k yen per month or aiming for higher cashback, Mitsui Sumitomo Card Gold (NL) is also an option. If you spend over 1 million yen annually, the annual fee is waived from the following year, and it offers a 1.0% cashback, allowing you to accumulate points easily. It can be used for investments through SBI Securities, so choosing stocks isn't a problem.

If you're a PayPay Securities user, the only choice is PayPay Card. It offers a 0.70% cashback and has no annual fee. Honestly, its cashback rate is lower than other cards, but if you frequently use PayPay services, it's sufficient.

For small investments through Rakuten Securities, Rakuten Card is recommended; for Matsui Securities, JCB Card W is suitable. Each securities company has designated compatible cards, so it's best to narrow down your choice based on where you want to invest. Ultimately, the comparison of credit card installment savings depends on which securities company you choose.