The lump sum
Most contracts allow an annual payment of a percentage of the original principal, penalty-free. That amount goes straight to principal, so it removes every future interest charge it would have carried.
The payment increase
You can usually raise your regular payment by a set percentage, once a year. Unlike the lump sum, the effect recurs: every later payment bites deeper into principal.
Accelerated payments
Moving from monthly to accelerated biweekly amounts to paying the equivalent of one extra monthly payment a year. It is the least visible lever and often the most profitable, because it demands no noticeable extra money.
The window matters
Some contracts confine the lump sum to a specific anniversary date, others allow it any time but only once per calendar year. A payment made on the wrong day can be refused or treated as a prepayment with a penalty.
They do not carry over
An unused privilege is generally lost at year end: it does not accumulate. Two years without a payment do not entitle you to double in the third.
To check before signing
Percentages, frequency, and windows vary by lender, and a slightly lower rate sometimes comes with restricted privileges. Have the clauses compared, not just the rates.
No rate, price, or recommendation on this page. Amounts and limits change: verify them with official sources before deciding.