Capitalisation is the moment your unpaid interest stops being interest and becomes principal. From that point forward you pay interest on it too. It is the single most expensive piece of fine print in student lending, and it happens quietly.
How it works
Unsubsidised federal loans and most private loans accrue interest from the day the money is disbursed, including every year you are still in school. You are not billed for it yet, so it sits in a separate bucket called accrued interest.
When a triggering event happens, the servicer takes that bucket and folds it into your principal balance. Your loan is now larger, and the interest rate applies to the bigger number.
In that example, roughly $5,200 of accrued interest becomes principal. The following year's interest is calculated on $25,200 instead of $20,000, which costs about $338 more that year alone, and every year after that.
What triggers it
- The end of your grace period, when repayment begins.
- The end of a deferment on unsubsidised loans.
- The end of a forbearance.
- Leaving an income-driven repayment plan, or in some cases failing to recertify your income on time.
- Consolidating loans, depending on the type.
Notice that most of these are things people do to get relief. Forbearance in particular feels like help and quietly enlarges the loan.
The one move that beats it: paying even small amounts toward interest while you are still in school, or during any deferment, keeps the accrued bucket small. You are not required to. That is precisely why it costs people so much.
Subsidised loans are the exception
On Direct Subsidised loans the government covers the interest while you are enrolled at least half time and during the grace period. Nothing accrues, so nothing capitalises. If you qualify for subsidised loans, take those first before anything unsubsidised.
What to do about it
- Check your accrued interest now. Log into your servicer. The number is listed separately from principal. Most borrowers have never looked.
- Pay interest during school if you can. Even $25 a month keeps the bucket from compounding into your balance.
- Prefer deferment over forbearance where you qualify, and prefer either over simply not paying.
- Recertify income-driven plans on time. Missing the deadline can trigger capitalisation on its own.
The short version
- Capitalisation turns unpaid interest into principal, permanently.
- Unsubsidised and private loans accrue from day one, including in school.
- Forbearance and grace period endings are the most common triggers.
- Small interest-only payments during school prevent most of the damage.
Common questions
Does interest capitalize on subsidized loans?
Not while you are enrolled at least half time or during your grace period, because the government pays that interest. It can capitalise after other events once repayment has begun.
Can I avoid capitalization entirely?
Largely, yes, by paying accrued interest before a triggering event happens. Making interest-only payments during school or deferment keeps the balance from growing.
Does consolidating student loans cause capitalization?
It can, depending on loan type and timing. Ask your servicer what your balance will be immediately after consolidation, before you agree to it.