Money explainer
Deferred interest: “no interest if paid in full”
A deferred-interest promo doesn’t stop interest. It postpones the decision about charging it until the promo ends — and then looks at the balance.
Reviewed Sep 14, 2026. Education only: mechanics and arithmetic, not financial advice.
Sources checked Sep 14, 2026
How it works
Interest is calculated from the purchase date through the promo. If the promotional balance is paid in full by the end, that interest isn’t charged. If any of it remains, interest can be charged back to the purchase date.
CareCredit describes its promos this way: interest accrues from the purchase date and isn’t charged if the promotional balance is paid in full by the end of the promotional period. The Alphaeon Credit card’s terms say interest is charged from the purchase date if the plan balance isn’t paid in full in time. The CFPB’s explainer describes being charged interest for each month on the balance owed in each month of the promo.
“Zero interest” and 0% APR aren’t the same promise
The words to look for are “if paid in full”. PatientFi markets zero-interest promos, and its disclosures say accrued interest is waived only if the balance is paid in full within the promotional period — which is deferred interest.
A true 0% plan works differently: Sunbit’s terms, for example, say no interest is charged or accrued during its 0% promotional period. Nothing accrued means nothing to add back at the end.
What the CFPB found
- People paid $1 billion in deferred interest on healthcare purchases from 2018 to 2020.
- For people who were charged deferred interest, it came to about 23% of the original purchase amount (2020).
- People with credit scores below 619 incurred interest on about 34% of their healthcare purchases.
- In May 2023 the typical medical credit card APR was 26.99%, against a mean of about 16% for general-purpose credit cards.
- Being more than 60 days late can mean losing the deferred-interest period, and minimum payments probably won’t clear the balance in time.
The clearing payment
Divide the balance by the months in the promo and round up to the cent. That’s the smallest level payment that clears it in time. It is arithmetic, not the minimum payment on a statement — and the CFPB notes the minimum payment probably won’t be enough.
Worked example · hypothetical figures
$1,200 on a 12-month deferred-interest promo, 24% APR after it, paying $50 a month
Interest estimated monthly at 2% on each month’s starting balance, which is how the financing calculator estimates it. An account agreement’s own method controls.
- Paid during the promo
- $600
- Balance when the promo ends
- $600
- Interest accrued from the purchase date (estimate)
- $222
- Balance once it’s charged
- $822
- Level payment that would have cleared it in time
- $100 a month
Paying off half the balance didn’t halve the interest. It was worked out on the whole path the balance took, starting from $1,200.
The figures are invented to keep the arithmetic easy to follow. They aren’t typical prices, and nothing here says what a price should be.
Questions to ask
- 1Is this deferred interest, or a true 0% APR?
- 2What APR applies if the balance isn’t cleared, and from what date?
- 3What’s the exact end date of the promo, and what will my statement call the promotional balance?
- 4Will the minimum payment clear it before the promo ends?
- 5What happens if a payment is late?
Run the numbers on a promo
A month-by-month balance, the back-interest estimate, and a reminder before it ends.
Open the financing calculatorSources
- Deferred Interest Promotional Financing vs. 0% APR OffersCareCredit · Checked Sep 14, 2026
- CareCredit FAQsCareCredit · Checked Sep 14, 2026
- Alphaeon Credit Card — summary of terms (Schumer box)Comenity Capital Bank · Checked Sep 14, 2026
- DisclosuresPatientFi · Checked Sep 14, 2026
- Rates & TermsSunbit · Checked Sep 14, 2026
- Medical Credit Cards and Financing PlansConsumer Financial Protection Bureau · Published May 4, 2023
- I got a credit card promising no interest for a purchase if I pay in full within 12 months. How does this work?Consumer Financial Protection Bureau · Last reviewed Jan 22, 2024