What is an acceleration clause?

An acceleration clause is a provision in a promissory note that allows the lender to declare the entire remaining balance immediately due and payable upon the occurrence of a defined default event, such as a missed payment or other breach of the note terms. Without an acceleration clause, the lender can only sue for the specific installments that have already been missed, not the full remaining balance.

Do all promissory notes need an acceleration clause?

Not legally required, but very strongly recommended for installment and secured notes. Without acceleration, a lender who wants to collect the full balance after a default must either wait for each future installment to come due and then sue for it (payment by payment) or argue to a court that the entire amount is due. The acceleration clause eliminates that ambiguity and gives the lender a clean right to demand everything at once after proper notice.

How long should the cure period be?

Cure periods (the time the borrower has to fix the default before acceleration kicks in) typically range from 10 to 30 days for payment defaults. A 10-day cure is common for formal commercial notes. For family and friend loans, a 15 to 30 day cure period is more typical and less likely to feel aggressive. Some notes distinguish between payment defaults (shorter cure) and non-payment defaults like failing to maintain insurance or collateral (longer cure, often 30 days). Whatever period you choose, state it clearly in the note.

What does an acceleration notice need to include?

The acceleration notice should: (1) identify the note by date, parties, and original principal; (2) describe the specific default (which payment was missed, on what date); (3) state that the cure period has expired or is being waived; (4) declare the full outstanding balance (principal plus accrued interest) immediately due and payable; (5) state the date by which payment must be received to avoid further action; and (6) be signed by the lender. Send it by certified mail with return receipt requested to document delivery.

Can I reverse acceleration after invoking it?

This is the one-way-door problem. Once you send an unambiguous acceleration notice, courts in many states hold that the full balance is due and the statute of limitations clock starts running on the entire remaining balance from that date. If you then accept a partial payment and continue as if nothing happened, you may have "de-accelerated" the note but with uncertain legal effect depending on your state. Avoid partial acceptance of payments after an acceleration notice without a written reinstatement agreement that expressly rescinds the acceleration and establishes new terms.

What triggers acceleration beyond a missed payment?

Well-drafted notes include multiple trigger events: (1) failure to pay any installment when due (after the cure period); (2) insolvency or bankruptcy filing by the borrower; (3) failure to maintain required insurance on collateral; (4) sale, transfer, or destruction of collateral without lender consent; (5) death of the borrower in some notes (though this is less common for family loans); and (6) any material false representation in the note or related documents. The triggers you include should match the actual risks in your specific situation.

Does invoking acceleration affect the statute of limitations?

Yes, and this is important. In many states, invoking acceleration restarts or resets the statute of limitations clock on the full balance from the date of the acceleration notice. This can be beneficial (you get a fresh window to sue on the entire balance) or it can be a trap if you were near the end of the limitation period on the earliest missed payments. Check your state's rules using the Statute of Limitations Lookup tool before sending an acceleration notice.

Acceleration Clauses: When to Use Them and How to Invoke

Without an acceleration clause, missing one payment means you can sue for one payment. With one, you can demand the whole balance. It is one of the most important provisions in any installment or secured promissory note, and it needs to be invoked carefully.

What acceleration does for the lender

On a standard installment note, payments are due monthly over several years. If the borrower stops paying in month 6 of a 36-month note, the lender can only sue for the 6 missed payments. Suing for the remaining 30 payments that are not yet due is generally not allowed without an acceleration clause.

An acceleration clause changes that. On a defined default event, the clause gives the lender the right to declare the entire outstanding balance (all remaining principal plus accrued interest) immediately due and payable. The lender can then sue for, or demand, the whole amount at once.

This matters enormously for secured notes. Acceleration is often the first step before repossession: the full balance is declared due, the borrower fails to pay, and the lender then proceeds to take the collateral or sue on the note.

Drafting a clear acceleration clause

A well-drafted clause answers four questions:

What triggers it? Define the default events specifically. Missing one payment? Two consecutive payments? Any breach of any note term? Insolvency? Destruction of collateral?
Is there a cure period? Most notes give the borrower a defined window (typically 10 to 30 days) to fix the default before acceleration becomes effective. The cure period protects the borrower against acceleration for minor or accidental lapses and protects the lender from accusations of acting too hastily.
Is acceleration automatic or optional? Most notes make acceleration optional for the lender (the lender "may" accelerate, not "the balance shall automatically accelerate"). This gives the lender the flexibility to accept a late payment without triggering a legal dispute about whether acceleration already happened.
How must the lender invoke it? The clause should require written notice to the borrower's last known address. This creates a paper trail and confirms the borrower received proper notice.

The cure period: getting it right

The cure period is the borrower's window to fix the default and avoid acceleration. After a missed payment, the lender sends a default notice. The borrower then has (for example) 15 days to bring the account current. If they do, the default is cured and the note continues. If they do not, the lender can send the acceleration notice.

For payment defaults, 10 to 15 days is common in commercial notes. For family loans, 15 to 30 days is more typical and less likely to strain the relationship prematurely.

Non-payment defaults (failure to maintain insurance on collateral, unauthorized transfer of the collateral) often have a longer cure period of 30 days, because the borrower may need time to remedy the situation (renew an insurance policy, for example).

How to send the acceleration notice

Invoke acceleration in writing. Do not call the borrower and say "you owe me everything now" and leave it at that. A written notice creates proof of the demand, the date it was made, and the amount claimed.

The notice should:

Identify the note (date, original principal, parties).
State the specific default (payment due January 1 was not received; cure period expired January 16).
Declare the full outstanding balance immediately due and payable, and state the exact amount.
Give an address where payment must be sent.
State what happens next if payment is not received (legal action, repossession, or both).

Send by certified mail, return receipt requested. Keep the green card (the signed receipt) with your note file. If the borrower refuses delivery, that is also documented. In some states, email is acceptable if the note specifies electronic notice as valid.

The one-way-door problem

Acceleration is difficult to reverse. Once you send an unambiguous acceleration notice declaring the full balance due, courts in many states treat that as starting the statute of limitations clock on the entire balance. If you then accept a partial payment and resume normal installment expectations, the legal status of the note becomes murky: have you de-accelerated? Did you waive the default?

If you want to accept a partial payment after acceleration (perhaps the borrower catches up on two months but cannot pay everything), do it under a written reinstatement agreement that explicitly:

Acknowledges the prior default and acceleration notice.
States that the lender agrees to reinstate the original note terms (or new modified terms) in exchange for the partial payment.
Rescinds the prior acceleration notice.
Is signed by both parties.

Without this formality, accepting payments after acceleration creates ambiguity that benefits the borrower in any later dispute.

Partial default vs material default

Not all defaults are equal. Missing one payment by three days (a technical default) is different from missing six consecutive payments and abandoning the collateral (a material default). A well-drafted acceleration clause may treat these differently, giving the lender discretion to waive minor technical defaults without surrendering the right to accelerate on material ones.

Document your decisions. If you choose not to accelerate on a minor technical default, send a written notice to the borrower acknowledging the breach but stating you are waiving the right to accelerate for that specific default only. This prevents the borrower from later arguing you established a "course of dealing" that waives your right to accelerate at all.

Secured Promissory Note Installment Promissory Note

After acceleration: what comes next

If the borrower does not pay the full accelerated balance by the deadline in your notice:

Secured note. Proceed to repossession of the collateral (for personal property) or foreclosure (for real estate). The note's default and security provisions govern the repossession process; your state's laws add procedural requirements.
Unsecured note. File suit in small claims court (for amounts within the state's limit, typically $5,000 to $25,000) or regular civil court for larger amounts. The acceleration notice and the note itself are your primary evidence.

Use our Statute of Limitations Lookup to make sure you are acting within the legal deadline for your state.