Savings & rates

CPF-OA vs T-Bill Calculator

Compare the net T-bill outcome with estimated CPF-OA interest lost, including application timing, fees and a calculated break-even yield.

✓ Results shown free✓ Dated source references✓ General information only

Live calculator

Uses MAS T-bill pricing and CPF calendar-month interest rules. Rules verified 18 Aug 2026.

Your comparison assumptions

Compare the actual discounted CPF-OA deduction with the interest that amount could have earned in OA.

MAS + CPF Board

T-bill yield and amount

Manual indicated yieldTest any annual yield; it is not treated as a live quote.Recent MAS auction resultUse a published cut-off yield from the MAS data cache.

Loading official MAS auction results…

Annual T-bill yield*

Enter a percentage, not the discount amount.Allotted face amount*

S$1,000 blocks, from S$1,000 to S$1 million.

Investment and refund timing

CPF interest loss starts in the deduction month—not the application month.

Application / auction date*CPF-OA deduction date*T-bill issue date*T-bill maturity date*Refund timing

Modelled OA-credit date16 Feb 2027

CPF interest assumptions

The 2.5% OA rate is editable. Add extra-interest exposure only if this withdrawn amount would otherwise qualify.

CPF-OA base rate*

Additional CPF interest rate

Amount exposed to extra interest

Optional; capped at S$20,000 and cannot exceed the discounted purchase price. This is a first-order estimate and excludes later SA/RA interest earned on extra interest credited in earlier years.

CPF agent-bank fees

CPF agent bankFee method

Current preset before GST

Purchase / transaction fee: $2.50 · Maturity transaction fee: $2.50 · Custody fee per charge: $2.00 · Expected custody charge count: 2

Expected custody charge count

2 quarterly charge(s) inferred from the issue and maturity dates. Editing this field overrides the estimate.GST rate

Add GST to entered or preset fees

Fair comparison basis

The CPF alternative uses the discounted purchase amount. Bank fees reduce the T-bill return; fee-balance interest is excluded because published schedules do not state exact debit dates.

⌁ Calculated in your browser. Inputs are sent only when you choose to save or export.

Clear outputs

What this tool will show

Each result stays connected to the inputs and rules used.

01T-bill net gain
02Base and extra CPF interest forgone
03Affected and post-maturity months
04Net difference and calculation verdict
05Break-even yield and price
06Monthly CPF interest ledger

Transparency standard

The workings stay visible from day one.

✓

Official rules

Applied parameters include a source and verification date.

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Assumptions

User inputs and defaults are clearly separated.

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Limits

Scope and exclusions appear beside the result.

Read the full methodology→

interest.sg provides general information, dated reference data and calculation tools. Results are estimates—not financial, investment, legal, tax, property, valuation, CPF, HDB, lending, insurance or protection advice. Verify material decisions with the relevant authority or a qualified professional.

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CPF-OA vs T-Bill Calculator

Your comparison assumptions

What this tool will show

The workings stay visible from day one.

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