Serene, 31, is a marketing executive earning $5,200 a month. She chose her cashback card from a comparison site that estimated $382 over six months on her spending. After six statements, the bank had paid her $226.80, and she wants to know why.
The gap comes from two terms that are judged one month at a time. A monthly cap limits the reward in a heavy month, and a minimum spend withholds the bonus rate in a light one. An average month hides both.
Serene's card spending averages $1,133 a month. Replayed month by month, her card paid $226.80 against the averaged $382.30, so the estimate was about 69% too high. The sections below follow how she checks her card against her own statements.
What Does Her Card Pay?
Serene's card has a shape common in the published terms:
- 8% cashback on dining, groceries and transport
- Cashback from the 8% rate capped at $80 a month
- A minimum of $800 of card spending in the month before the 8% rate applies
- 0.3% on all other spending, and on all spending in a month that misses the minimum
The card is illustrative, with terms drawn from the range in the table below. No single named product is used. Of 76 Singapore credit cards whose published headline terms were checked on 28 August 2026, 40 pay cashback, 25 pay miles and six pay bank reward points. The rest mix units or state no earn rate.
| Term | What the published terms show |
|---|---|
| Annual fee | $196.20 on 39 cards, no fee on 12 |
| Minimum annual income | $30,000 on 55 cards, $120,000 on six |
| Most common bonus cashback rate stated without "up to" | 5% |
| Monthly minimum spend, where stated | $300 to $2,000, most often $500 or $800 |
| Monthly cashback cap, where stated | $70 to $100 |
Source: Published headline terms for 76 Singapore credit cards, checked 28 August 2026
Many cards state their bonus as "up to" a rate. An "up to" figure is the highest tier, and only some of the spending earns it, so it should not be used as the rate for a whole ledger. Serene's 8% sits above the most common 5%, and her $800 minimum and $80 cap are both common terms.
Why Does Averaging Her Spending Give The Wrong Answer?
A cap and a minimum spend both reset every month. A light month that misses the minimum earns only the base rate, and a later heavy month cannot make up for it. A heavy month that passes the cap loses the excess, and a later light month cannot use the spare room.
An average month passes the minimum and stays under the cap, so it earns the full bonus on everything. Serene's real months rarely did both.
What Did Her Card Pay Month By Month?
Serene puts all of her card spending on this one card. The table replays her six statements against its terms.
| Month | Total card spend | Dining, groceries, transport | Minimum cleared? | Cashback |
|---|---|---|---|---|
| January | $1,400 | $900 | Yes | $73.50 |
| February | $650 | $450 | No | $1.95 |
| March | $2,100 | $1,500 | Yes, cap reached | $81.80 |
| April | $700 | $500 | No | $2.10 |
| May | $1,200 | $800 | Yes | $65.20 |
| June | $750 | $550 | No | $2.25 |
| Total | $6,800 | $4,700 | 3 of 6 months | $226.80 |
Source: Worked example on illustrative card terms
In March, 8% of $1,500 is $120, and the cap limits it to $80. The other $600 earns $600 × 0.3% = $1.80, for $81.80. In February, $650 is below $800, so every dollar earns 0.3%, or $1.95.
The comparison site took $6,800 ÷ 6 = $1,133.33 a month, of which $783.33 is dining, groceries and transport. That month clears the $800 minimum and stays under the cap, so it earns $783.33 × 8% + $350 × 0.3% = $63.72. Over six months that is 6 × $63.72 = $382.30, or $155.50 more than the card paid her.
Read Also: Two-Card And Three-Card Wallets: When A Second Credit Card Pays For Its Annual Fee
How Close Was Each Missed Month?
The replay also shows how far each light month fell short. February missed the minimum by $150, April by $100 and June by $50.
In June, $50 more of other spending on the card would have cleared the minimum. The month would then have paid $550 × 8% + $250 × 0.3% = $44.75 instead of $2.25. An averaged estimate cannot show this, because it has no light months.
Which Payments Should She Leave Out?
PayNow and bank transfers, ATM withdrawals, cash advances and loan repayments leave a bank account every month, but they have no merchant on the other end. Card schemes pay no reward on them. They still count as spending in a budget, and a monthly PayNow allowance to a parent is money the household has spent.
Serene also sends her parents $500 a month by PayNow. A ledger that counts it shows February at $1,150, which clears the $800 minimum on paper and suggests $450 × 8% + $200 × 0.3% = $36.60 for the month. The card paid $1.95, because the issuer never sees the PayNow transfer as card spending. A telco or utility bill charged to the card by GIRO is a merchant charge, and some cards pay a bonus on it.
What Else Decides The Answer?
The card that pays a household the most depends on these inputs, all read from its own statements:
- Category mix. How much of each month falls into the categories the card pays a bonus on.
- Monthly variation. How many months fall below the minimum spend, and by how much.
- Heavy months. How often the bonus spending passes the cap, and by how much.
- Annual fee. A fee of $196.20 a year is $98.10 for six months, or about 43% of Serene's cashback, unless the bank waives it.
- Conditions. Some bonus rates need a linked savings account, a minimum balance or a category chosen in the bank's app. A rate the cardholder cannot meet earns nothing.
Welcome gifts and sign-up promotions are one-off and change often. A comparison of ongoing value leaves them out.
Read Also: Miles Or Cashback In Singapore: How Much A Mile Has To Be Worth
How Many Months Of Statements Does She Need?
Six months shows whether light months miss the minimum. Twelve months also catches annual insurance premiums, festive spending and travel bookings, which are often the months that reach a cap.
The statements need to be read by statement period where the card measures its minimum spend that way. A purchase on the last day of a calendar month can fall into the next statement month.
Read Also: How To Budget In Singapore: Building A Monthly Budget From Your Bank Statements
What Did Serene Decide?
Serene keeps the card for now and asks the bank to waive the $196.20 annual fee. Without a waiver, $98.10 of fee for six months leaves her $128.70 of the $226.80. She will compare it against a card with no minimum and no cap once she has twelve months of statements, read by statement period and without the PayNow transfers.
A card with a high bonus rate, a monthly cap and a minimum spend suits cardholders whose spending clears the minimum almost every month and stays near the cap. Cardholders whose spending swings between light and heavy months, as Serene's does, may earn more from a card with a lower rate, no minimum and no cap, and the result depends on each cardholder's own months.