A promissory note often looks simple: one person promises to pay another a fixed sum on a stated date or on demand. Problems begin when the note is silent on interest. The creditor naturally asks: Can I still collect interest? If yes, from when, at what rate, and on what legal basis?

In Philippine law, the answer is precise:

You may always sue to collect the principal stated in the promissory note. But you cannot collect conventional or contractual interest unless it was expressly stipulated in writing. When the debtor defaults, however, the creditor may still recover legal interest as damages for delay, subject to the rules on demand, maturity, and the nature of the obligation.

That distinction is the core of the subject. Everything else follows from it.

I. The Basic Rule: No Written Stipulation, No Conventional Interest

Under Philippine civil law, interest is not presumed. A lender cannot simply say that money naturally earns interest and therefore interest should be imposed. As a rule, interest by agreement must be expressly agreed upon in writing.

This is the controlling framework:

A promissory note is evidence of a loan or forbearance of money.
The principal amount is recoverable if the note is valid and the debt is due.
Conventional interest is recoverable only if the parties clearly agreed to it in writing.
If the note contains no interest clause, the creditor cannot later invent one, infer one from custom, or prove an oral side agreement to impose interest as part of the original bargain.

So if the note says only:

“I promise to pay ₱500,000 on December 31, 2025.”

then the creditor may sue for ₱500,000, but not for “12% interest” or “market interest” unless that interest was separately and validly stipulated in writing.

This is the first and most important legal point.

II. The Difference Between Contractual Interest and Legal Interest

A lot of confusion comes from treating all interest as the same. In Philippine law, they are not.

1. Contractual or conventional interest

This is interest that the parties themselves agreed on as part of the loan. It is imposed because of the contract.

Example: “Borrower shall pay interest at 10% per annum.”

If there is no written stipulation, this kind of interest is generally not collectible.

2. Legal interest

This is interest imposed by law, usually as damages for delay in the payment of money.

Even when a promissory note is silent on interest, the court may still award legal interest once the debtor is in default, because the debtor’s delay caused damage to the creditor.

That is why a creditor with an interest-free promissory note is not necessarily limited forever to principal alone. The creditor may still recover legal interest upon default, but not as part of the original bargain. It is recovered as a legal consequence of late payment.

III. If the Note Has No Interest Clause, What Can Be Collected?

In a typical case, the creditor may recover some or all of the following:

A. The principal amount

This is the face value of the promissory note.

B. Legal interest for delay

This may be awarded from the date of default, not automatically from the date the loan was released.

C. Attorney’s fees and costs of suit

These are not automatic. They usually require either:

a contractual stipulation, or
a justified award under the Civil Code and procedural rules.

If the note is silent, attorney’s fees may still be awarded in proper cases, but courts do not grant them as a matter of course.

D. Penalties, service charges, or collection charges

These also require valid contractual basis. If they were not stipulated, they are generally not collectible.

IV. When Does Default Begin?

This question decides when legal interest may start running.

In Philippine obligations law, delay or mora does not always arise automatically. Usually, the debtor must first be in default, and default generally requires that the obligation be due and demandable, and that a demand has been made, unless demand is unnecessary by law or by the nature of the obligation.

1. If the note has a fixed maturity date

Example: “I promise to pay ₱500,000 on December 31, 2025.”

Once that date arrives and payment is not made, the debt is due. In many collection cases, the creditor still makes a formal demand to strengthen the record. As a practical matter, that is wise.

2. If the note is payable on demand

Example: “I promise to pay ₱500,000 on demand.”

The debt becomes enforceable upon demand. Here, a written extrajudicial demand is especially important.

3. If judicial demand is the first demand made

If no prior demand was sent, the filing of the complaint itself may serve as judicial demand. In such a case, legal interest may run from the filing of the complaint, depending on the facts and the court’s appreciation.

4. When demand is unnecessary

In some situations, demand is not needed, such as when:

the obligation or law expressly so provides,
time is of the essence,
demand would be useless because performance is impossible or refused.

But in ordinary promissory note litigation, a written demand letter is still the safest path.

V. What Is the Legal Interest Rate in Philippine Collection Cases?

For modern Philippine obligations involving unpaid money, the familiar rule is 6% per annum as legal interest in many contexts, particularly after the doctrinal shift associated with later jurisprudence and the Bangko Sentral change that lowered the prior 12% rate.

For practical Philippine collection analysis today, the working rule usually applied is:

6% per annum legal interest on the unpaid amount as damages for delay, from the proper reckoning point.
Once there is a final and executory judgment awarding a sum of money, the judgment amount may also earn 6% per annum until full satisfaction.

Because the historical rules changed over time, the relevant dates matter. Older obligations and litigation periods may involve transitional treatment. But for most present-day cases and current drafting, lawyers and courts typically work with the 6% per annum framework.

VI. From What Date Does Legal Interest Run?

This is where many creditors overclaim and many debtors underappreciate exposure.

If no conventional interest was stipulated, legal interest does not usually run from the date the loan was granted. It generally runs from the point the debtor is considered in delay.

Possible reckoning points include:

A. From the date of extrajudicial demand

This is common where the note matured, remained unpaid, and the creditor sent a written demand.

B. From the filing of the complaint

This is common where there was no sufficient prior demand or where the amount became judicially established in the case.

C. From finality of judgment

In some older formulations of the rule, where the claim was not liquidated or certainty arose only upon judgment, interest could run from finality of judgment on the adjudged amount until satisfaction.

The exact reckoning point depends on:

whether the debt was already certain and demandable,
whether a valid prior demand was made,
whether the note itself fixed maturity,
whether the amount due was liquidated or disputed.

For a straightforward promissory note with a fixed amount, fixed due date, and clear default, courts are more receptive to awarding legal interest from the date of demand or default.

VII. If the Note Says Nothing About Interest, Can Oral Testimony Prove an Interest Agreement?

Usually, this is a bad position for the creditor.

The rule requiring a written stipulation means that a supposed oral agreement on interest is generally not enough to support collection of conventional interest. A creditor who says:

“We agreed verbally to 2% per month, but we forgot to put it in the note”

will usually run into the rule that interest must be expressly stipulated in writing.

Oral testimony may still be relevant to explain surrounding circumstances, but it generally cannot overcome the requirement of a written stipulation for conventional interest.

VIII. Can the Creditor Recover Interest Because the Debtor Used the Money for a Long Time?

Not as contractual interest, unless there was a written stipulation.

Philippine law does not assume that every loan bears interest. A loan can be gratuitous as to interest. The fact that the borrower kept the money for months or years does not automatically create a right to contractual interest.

What the law does recognize is that once the debtor is in delay in paying a sum already due, the creditor suffers damage. That is the legal basis for legal interest as damages, not a substitute oral bargain.

IX. Can the Parties Later Agree on Interest Even If the Original Note Was Silent?

Yes. They may later execute a valid written agreement, amendment, addendum, restructuring agreement, acknowledgment, or renewal note that imposes interest going forward.

But several cautions apply:

1. The later agreement should be in writing

Because the problem is the absence of a written interest stipulation, the cure is also writing.

2. The later agreement should clearly state:

the principal balance,
the interest rate,
when interest begins,
whether prior defaults are waived,
the due date or installment schedule,
any penalties or attorney’s fees.

3. It should be voluntarily entered into

If extracted through fraud, intimidation, or clear unconscionability, it may be attacked.

4. It should not disguise usurious or unconscionable terms

Although the old Usury Law ceiling is no longer the ordinary controlling cap in the same way, courts may still strike down iniquitous, excessive, or unconscionable interest rates and penalties.

So yes, the parties can fix the omission later, but they should do it carefully.

X. What If Partial Payments Were Made?

Partial payments matter a lot in collection.

They may affect:

the remaining principal balance,
acknowledgment of the debt,
interruption of prescription in some contexts,
the computation of legal interest,
the credibility of defenses such as full payment.

If there is no contractual interest, partial payments are generally applied to principal unless another lawful application is shown. Once legal interest has accrued due to delay, the accounting can become more complex, especially if judgment has already been rendered.

The creditor should preserve:

official receipts,
bank transfer records,
acknowledgment messages,
ledgers,
postdated checks if any,
signed statements of account.

XI. How Do You Actually Collect on the Note?

Collection is not only about doctrine. It is also about sequence.

Step 1: Review the promissory note carefully

Check:

exact principal amount,
maturity date,
whether it is payable on demand,
signatures,
witnesses or notarization, if any,
acceleration clause,
attorney’s fees clause,
venue clause,
penalty clause,
acknowledgment of receipt of value.

If the note is silent on interest, accept that conventional interest may not be collectible.

Step 2: Gather supporting proof

A promissory note is strong evidence, but supporting documents help:

proof of release of funds,
bank records,
receipts,
chats or emails acknowledging the debt,
any rescheduling agreements,
bounced checks,
prior demand letters.

Step 3: Send a written demand letter

This is one of the most important practical moves.

The letter should state:

the existence of the promissory note,
the amount due,
the maturity date,
that the debt remains unpaid,
a deadline to pay,
that failure to pay will result in legal action,
a claim for legal interest for delay and costs where proper.

A demand letter helps establish default and often becomes a key exhibit.

Step 4: File the proper civil action if unpaid

Usually this is an action for sum of money or collection of a debt.

The proper court depends on jurisdictional amount and applicable procedural rules.

Step 5: Prove the debt and the date of default

If the note is clear and authentic, the main litigation fights often become:

authenticity of signature,
payment,
novation,
prescription,
alleged lack of consideration,
whether demand was made,
how interest should be computed.

Step 6: Enforce the judgment

Winning the case is not the same as being paid. If the debtor still does not pay, execution may follow against leviable assets, subject to exemptions and procedure.

XII. What Should the Demand Letter Ask For?

Where the note has no interest clause, the demand letter should generally ask for:

payment of the principal amount,
legal interest for delay from the date legally proper,
attorney’s fees and costs where justified.

It should usually not demand invented “contractual” interest unless there is a genuine written basis. Overclaiming can weaken credibility and invite unnecessary defenses.

A disciplined demand is better than an inflated one.

XIII. Is Notarization Required for the Note to Be Enforceable?

No. A promissory note need not be notarized to be valid between the parties.

A notarized note may enjoy evidentiary advantages and stronger formal appearance, but an unnotarized promissory note can still be valid and enforceable if the essential requisites are present.

The lack of notarization does not create a right to interest where none was written.

XIV. Does the Negotiable Instruments Law Matter?

Sometimes, yes. A promissory note may also qualify as a negotiable instrument if it meets the legal requisites. That can matter for transfer, endorsement, holder status, and certain presumptions.

But on the specific issue of collecting interest without a stipulated interest rate, the practical civil-law rule remains central:

The principal is collectible if validly due.
Contractual interest requires stipulation.
Legal interest may be imposed upon default.

So even if the note is negotiable in form, silence on interest still does not authorize the holder to impose contractual interest out of thin air.

XV. Can a Court Award Interest Even If the Complaint Did Not Specifically Mention It?

Courts generally act within the claims and issues properly raised, though legal interest may be treated as a legal consequence in some cases. Still, the safer practice is to specifically pray for legal interest in the complaint.

The complaint should make clear that:

there is no contractual interest clause, but
the debtor is in delay, and therefore
legal interest as damages should be awarded from the proper date until full payment.

Clear pleading prevents avoidable issues.

XVI. What Defenses Does the Debtor Usually Raise?

A creditor collecting on an interest-free promissory note should expect defenses such as:

1. Payment

The debtor claims the loan was fully or partly paid.

2. Lack of consideration

The debtor denies receiving the money.

3. Forgery or denial of signature

Common when the note is private and poorly documented.

4. Novation

The debtor argues the original note was replaced by a new arrangement.

5. Prescription

The debtor argues the action was filed too late.

6. No demand, no delay

The debtor argues legal interest should not run because no valid demand was made.

7. Unclean hands by the creditor

Sometimes raised when the creditor overstates amounts or relies on undocumented side agreements.

Knowing these defenses helps the creditor prepare the evidence that matters.

XVII. Prescription Concerns

Collection actions do not last forever. The applicable prescriptive period depends on the nature of the instrument and cause of action.

That is why creditors should not sit on a promissory note for years assuming it can always be enforced later. The exact prescriptive rule may depend on whether the action is founded on a written contract, a negotiable instrument, or related documents and conduct.

Because prescription can be decisive and fact-sensitive, a creditor with an aging note should treat time as a serious risk.

XVIII. Attorney’s Fees: Are They Recoverable?

Not automatically.

In Philippine practice, attorney’s fees may be awarded when:

there is a valid stipulation in the promissory note,
the debtor’s act or omission falls within recognized statutory grounds,
the court finds the award just and equitable under the circumstances.

But courts require a proper basis. They do not simply award attorney’s fees because the creditor hired counsel.

If the note is silent, attorney’s fees are still possible, but they must be justified, pleaded, and supported.

XIX. Penalty Charges Without Stipulation?

No.

A penalty clause, liquidated damages clause, or collection surcharge must also rest on valid contractual basis. If the note is silent, the creditor cannot add:

5% monthly penalty,
collection fee,
service fee,
rollover charge,
“default interest,”

unless those were validly stipulated.

Again, the proper fallback is legal interest as damages for delay, not invented contract terms.

XX. What If the Debtor Issued a Bounced Check in Payment?

That can materially help the creditor.

A bounced check may:

reinforce proof that the debt exists,
show acknowledgment of the obligation,
support separate remedies under other laws where applicable,
undermine claims of non-liability.

But the bounced check does not by itself create a right to contractual interest if the original promissory note had none. It may, however, strengthen the case for collection and damages.

XXI. If the Debtor Admits the Debt by Text or Email, Does That Matter?

Very much.

Admissions in writing, even outside the promissory note, may help prove:

the existence of the debt,
the unpaid balance,
the due date,
requests for extension,
acknowledgment of default.

Still, such admissions do not usually cure the absence of a written original interest stipulation unless the later written acknowledgment itself clearly and validly agrees to interest.

A message saying, “I know I still owe you ₱500,000; please give me until next month,” is excellent for proving the debt. It is not the same as, “I agree to pay 12% per annum from today.”

XXII. Can Equity Save the Creditor from a Badly Drafted Note?

Only to a point.

Philippine courts may use equity to prevent injustice, but equity does not usually override a clear statutory rule that conventional interest must be stipulated in writing.

So equity may support:

recovery of legal interest after delay,
fair computation of damages,
rejection of sham defenses,

but it will not typically transform a silent note into an interest-bearing one by contract.

XXIII. Litigation Strategy in a No-Interest Promissory Note Case

For the creditor, the best strategy is usually not to argue for everything imaginable. It is to argue the right things strongly.

The strongest theory is usually:

There is a valid promissory note.
The principal amount is certain.
The debt matured or was demanded.
The debtor failed to pay.
Therefore the principal is due.
Because of delay, legal interest should be imposed from the proper date.
Attorney’s fees and costs should be awarded if properly justified.

That theory is legally disciplined and easier to sustain.

Weak theories include:

“Everyone knows loans bear interest.”
“We agreed orally.”
“The debtor had my money for years, so I should get commercial interest.”
“I am entitled to the bank rate even though nothing was written.”

Those arguments are usually vulnerable.

XXIV. Drafting Lessons: How to Avoid This Problem Next Time

The topic is about collection, but the real lesson is drafting.

A proper Philippine promissory note should ideally state:

principal amount,
date and place,
date of loan release,
due date or installment schedule,
interest rate, if any,
whether interest is per annum or per month,
penalty in case of default,
attorney’s fees and litigation expenses,
acceleration clause,
venue clause,
acknowledgment of receipt of value,
signatures of parties,
witnesses or notarization where useful.

A single sentence often prevents a full lawsuit:

“This loan shall bear interest at the rate of __% per annum, computed from release until full payment.”

Without that, the creditor may be left fighting only for principal plus legal interest after default.

XXV. A Simple Illustration

Suppose A lends B ₱1,000,000. B signs a note saying:

“I promise to pay A ₱1,000,000 on January 31, 2025.”

There is no interest clause.

B does not pay.

A sends a written demand on March 1, 2025, giving B five days to settle. B still does not pay. A sues.

What A can generally claim:

₱1,000,000 principal
legal interest, commonly 6% per annum, from the legally proper reckoning point
attorney’s fees and costs, if justified

What A generally cannot claim:

12% annual interest from the date of the loan
2% monthly interest by alleged verbal agreement
default penalties not found in the note
collection charges not found in the note

That is the doctrine in practical form.

XXVI. Common Mistakes by Creditors

1. Waiting too long before making demand

This weakens proof of delay and raises prescription concerns.

2. Demanding unsupported rates

This invites resistance and may undermine settlement.

3. Failing to preserve proof of the loan release

The note is strong, but proof of actual release helps.

4. Filing without a clean computation

Courts appreciate a disciplined, defensible statement of claim.

5. Confusing legal interest with contractual interest

These are different remedies with different sources.

6. Relying on oral side agreements

These are usually poor substitutes for written terms.

XXVII. Common Mistakes by Debtors

1. Assuming no interest clause means no consequences for delay

Wrong. Legal interest may still accrue.

2. Ignoring demand letters

Silence can worsen exposure and litigation posture.

3. Making partial payments without documentation

This creates later disputes over the remaining balance.

4. Issuing checks without funds

This may create additional legal problems.

5. Believing that an unnotarized note is automatically void

It is not.

XXVIII. Key Philippine Takeaways

For a promissory note without a stipulated interest rate, the Philippine rule can be reduced to five points:

1. The principal is collectible

Silence on interest does not invalidate the debt.

2. Contractual interest is generally not collectible

Not unless there is a valid written stipulation.

3. Legal interest may still be awarded

Usually as damages for delay once the debtor is in default.

4. Demand matters

A written demand letter is often crucial in fixing delay and supporting interest.

5. Precision matters more than aggression

A creditor with a silent note usually wins more by making a clean claim for principal plus legal interest than by insisting on unsupported commercial rates.

XXIX. Bottom Line

In the Philippines, a promissory note that does not state an interest rate is not worthless. It remains enforceable as to the principal amount. What the creditor loses is not the debt itself, but the right to claim conventional interest by agreement.

That said, the law does not leave the creditor empty-handed after default. Once the debt is due and the debtor delays payment, the creditor may generally recover legal interest as damages, commonly reckoned at 6% per annum under the modern framework, from the legally proper date until full payment, depending on the facts and procedural posture of the case.

So the practical answer to the topic is:

You collect first on the note’s principal, then on legal interest arising from delay, not on imaginary contractual interest that the note never contained.

That is the controlling Philippine approach.