What Is the RSTU Scheme?

The Retirement Sum Topping-Up Scheme (RSTU) is a CPF mechanism that allows Singapore residents to make voluntary cash top-ups to their own CPF Retirement Account (RA) or Special Account (SA), or to a family member’s CPF accounts. The topped-up funds earn the prevailing CPF interest rates — 4% p.a. for the SA and RA — and count towards the recipient’s retirement sum for CPF LIFE payout purposes.

As at 2025, the maximum top-up limit per recipient per year is the difference between the Enhanced Retirement Sum (ERS, currently S$426,000) and the recipient’s current RA/SA balance. Tax relief is given for top-ups to yourself (up to S$8,000/year) and separately for top-ups to family members (up to S$8,000/year), for a combined maximum tax relief of S$16,000/year.

Tax Relief Under RSTU

This is one of the most powerful tax-saving mechanisms available to Singapore taxpayers, especially those in higher income tax brackets. For a taxpayer in the 15% marginal rate bracket, a S$8,000 top-up saves S$1,200 in income tax, while the funds simultaneously earn a guaranteed 4% p.a. in CPF — effectively a first-year return of 15% + 4% on that money.

Key 2025 tax relief figures:

• Top-up to own RA/SA: up to S$8,000 tax relief
• Top-up to parent/spouse/sibling’s RA/SA: up to S$8,000 tax relief (separate cap)
• Cash top-ups only qualify — CPF-to-CPF transfers do not qualify for RSTU tax relief
• Deadline: Top-ups must be made by 31 December for that tax year’s relief

Who Can Receive a Top-Up?

You can make RSTU top-ups to the following recipients:

• Yourself (own RA or SA)
• Your spouse
• Your parents and parents-in-law
• Your grandparents and grandparents-in-law
• Your siblings (subject to an income threshold — recipient’s annual income must not exceed S$4,000)

Recipients must be Singapore Citizens or Permanent Residents. The recipient’s RA/SA balance must be below the applicable retirement sum cap for top-ups to qualify.

How to Make an RSTU Top-Up

RSTU top-ups can be made online via the CPF Board’s e-Cashier portal (my.cpf.gov.sg) using PayNow, GIRO, or credit/debit card. For top-ups to family members, you’ll need their NRIC number. The process typically takes 3–5 business days to reflect in the recipient’s CPF account.

Always verify the recipient’s current account balance and applicable retirement sum before topping up to avoid exceeding the cap — CPF Board will refund excess top-ups, but this may take time. See the CPF Full Retirement Sum 2026 page for current figures.

RSTU vs SRS: Which Is Better?

Both schemes offer tax relief but serve different purposes. The Supplementary Retirement Scheme (SRS) allows broader investment choices including SGX stocks, ETFs, and unit trusts, while RSTU locks funds into CPF earning a fixed 4% rate. For most CPF members who have not yet topped their RA to ERS, RSTU offers a better guaranteed return plus tax relief. For those seeking market-linked upside in retirement savings, SRS is more flexible. Many Singapore investors use both: RSTU first up to the S$8,000 relief cap, then SRS for additional tax-deferred savings. For an overview of CPF retirement tools, see CPF LIFE.