The determination of which is more cost-effective depends on the specific situation and individual needs. Here are some factors to consider:
The number of years of contributions: In the first case, you'll need to have paid for 15 years; in the second case, you'll need to have paid for 25 years. If you have a stable job and plan to stay in your current area for a long time, and you can afford to pay for 15 years, the first option may be more cost-effective.
Tiers and benefits: In the first scenario, you pay 100 percent of the tier and may enjoy higher Social Security benefits, while in the second scenario, you pay 60 percent of the tier and the corresponding benefits may be reduced. Therefore, if you value the coverage and extent of your Social Security benefits more, the first approach may be more cost-effective.
Personal finances: You should consider your personal finances. Paying higher Social Security premiums may be more stressful on your finances, especially over a longer period of time. If you want to be more financially secure, the second option may be better for you.
Retirement planning: Consider your retirement plans and personal goals. You may need to evaluate the pension or old-age benefits offered by different levels of Social Security contributions and match them to your retirement plan. Based on your personal needs and expectations, determine which will better meet your retirement goals.