Here’s a Philippine-context legal explainer on fixing a wrong purchase price in a Deed of Absolute Sale (or Deed of Sale) — what counts as a mere typo vs. a substantive error, how to correct it cleanly, what to expect from the BIR/LGU/Registry of Deeds, and the risks if you get it wrong.

Quick take (the one-minute version)

Price is an essential element of a sale. If the instrument states the wrong price, you must correct the instrument, not just “explain it away.”
Two main routes:
1. Out-of-court correction (Deed of Correction/Supplemental Deed/Rectification Agreement), if all parties agree and facts are straightforward.
2. Judicial reformation of instrument (Regional Trial Court), if there’s disagreement or the document no longer reflects the parties’ true intent due to mistake/fraud/accident.
Taxes & registration follow the truth, not the typo. If the corrected price is higher, expect additional taxes/penalties; if lower, expect scrutiny (possible donor’s tax issues or proof demands).
Never backdate or understate: misdeclarations can trigger tax evasion or falsification exposure.

Why the price matters in Philippine law

Under the Civil Code, a sale requires consent, a determinate object, and a price certain in money. The written deed is the public/probative proof of those.
If the written deed does not express the true agreement because of mistake, fraud, inequitable conduct, or accident, a party may seek reformation of instrument (so the paper matches the real deal).
If the price is simulated (not the real consideration), the sale can be void; the transaction may be re-characterized (e.g., donation) only if its requisites exist.
For real property, the Statute of Frauds effectively requires the price to be written; thus, getting the price wrong is not trivial.

Classifying the error (matters for the remedy)

Clerical/typographical error
- Example: the words say “Two Million Pesos” but the figures show “₱200,000,” and all surrounding documents (receipt, bank transfer, reservation agreement) show ₱2,000,000.
- Fix: Deed of Correction/Rectification signed by the same parties, notarized, precisely identifying the original deed (Doc/Page/Book/Series) and replacing the erroneous clause.
Substantive pricing error (wrong number altogether; discount omitted; partial payment recorded as total; price renegotiated)
- Fix: Deed of Correction/Supplemental Deed plus tax rectifications (BIR/LGU). If parties dispute the “true” price, file reformation of instrument in the RTC.
After-the-fact change of price (e.g., “we later agreed to reduce the price”)
- This is not a correction of mistake; it’s a new agreement (remission/discount/partial rescission). It can have donor’s tax implications if value is given up gratuitously.

The practical playbook

A) Out-of-court correction (when everyone agrees)

Document to prepare:

Deed of Correction / Rectification Agreement / Supplemental Deed (titles vary).
Parties: same seller(s) and buyer(s) (and spouses, if they signed the original).
Contents checklist:
- Exact caption and parties’ identities as in the original.
- Whereas clauses: describe the original deed (date, notary, Doc/Page/Book/Series), the specific error, and how it happened.
- Corrective clause: “The parties correct Paragraph __ such that the purchase price shall read: ‘₱____ (____ PESOS), Philippine currency,’ and all references to price in the Deed shall be understood accordingly.”
- Ratification: “All other terms remain in full force.”
- Undertaking to update taxes/fees if needed.
Notarize and have it entered in the notarial register.

Filing/annotation sequence (typical for real property):

BIR (if CAR not yet issued): submit the corrected deed with supporting proofs; BIR computes taxes based on the higher of (i) corrected price or (ii) zonal/fair market value.
BIR (if CAR already issued): request amendment/revalidation of CAR; pay any deficiency CGT/DST (and surcharges/interest) if the corrected base is higher.
LGU Treasurer: transfer tax recomputation (based on higher of corrected price or FMV).
Registry of Deeds: present the corrected deed (and amended CAR/TT), for annotation together with the original deed; if title already transferred, the correction is usually annotated on the title’s memorandum of encumbrances.

When price goes down:

Expect the BIR to probe: was the original price wrong, or is this a post-sale reduction?
Prepare objective proof of mistake existing before or at the time of notarization (e.g., emails, reservation/offer sheets, bank transfer amount, receipts).
If the reduction is gratuitous, the foregone value can be treated as a donation (possible donor’s tax exposure).

B) Judicial route (when parties disagree or the stakes are high)

File a Complaint for Reformation of Instrument (RTC where the property is, or where any party resides, per rules).
Allege and prove: true price agreed upon; the instrument failed to state it due to mistake/fraud/accident; and you consistently acted in line with the true price (payments, receipts, communications).
Relief: judgment ordering the deed reformed to reflect the true price; judgment can then be used to amend taxes/records.
Consider adding alternative causes (e.g., annulment or rescission) if the facts justify.

Evidence that convinces agencies and courts

Money trail: bank/GCash/PayMaya/manager’s check slips, deposit confirmations, escrow statements.
Transactional papers: reservation/offer to sell, counter-offer, email threads, Viber/WhatsApp messages (export full threads), pro-forma from the developer/broker, price list.
Receipts & acknowledgments: official receipts, provisional receipts, notarized undertakings.
Valuation context: zonal value tables, tax declarations (to show that your corrected price isn’t an obvious undervaluation).
Affidavits: of broker/closing officer/treasurer explaining the error (for clerical cases).

Tax and fee implications (high level, for planning)

Numbers and labels below are the usual anchors. Always compute on the higher of the (corrected) contract price or the BIR/FMV base.

Capital Gains Tax (CGT) on sales of capital assets (commonly individual sellers of non-dealer real property): typically 6%.
Creditable Withholding Tax (CWT) instead of CGT for sales of ordinary assets (e.g., developer/inventory property), rates vary.
Documentary Stamp Tax (DST) on the deed (commonly 1.5%).
Local Transfer Tax (city/municipality; often around 0.5%–0.75%, locality-dependent).
Registration Fees at the Registry of Deeds (schedule-based).
Penalties/surcharges/interest if the corrected base is higher than what was originally taxed.
Donor’s Tax considerations if the price is reduced without consideration (i.e., a partial gratuitous disposition).
VAT may apply in ordinary-asset sales by VAT-registered sellers (e.g., developers), independent of CGT (you don’t pay CGT if the property is an ordinary asset).

Tip: Submit a short tax memo with your correction package: one page explaining why the original figure was wrong, what the true price is, and how you computed the revised taxes.

Registration nuances (Registry of Deeds)

If transfer not yet completed: file the corrected deed with the deed of sale; the ROD will rely on the latest, controlling instrument (plus CAR/TT).
If title already transferred: the correction is done by annotation (and, if necessary, by issuing a new CAR and paying the delta taxes).
The corrective instrument must mirror the parties and execution details of the original (including marital consent where applicable).

Risk flags & how to avoid them

Intentional undervaluation to cut taxes: this risks tax evasion and falsification of public documents; agencies increasingly cross-check payments with bank reports and developer ledgers.
Backdating the correction: don’t. Use the actual execution date and explain the error.
Leaving out a spouse/co-owner who signed the original: the correction can be attacked as void as to them.
Vague wording: state the exact sentence or clause being replaced and write the price in both words and figures.
Using RA 9048/10172 (civil registry correction) for deeds: these statutes cover birth/marriage/death records, not deeds. They are not the remedy here.

Special situations

Developer sales (condos/subdivisions): Prices are often supported by reservation agreements, payment schedules, and official receipts — these are powerful proofs for a clerical error correction. If the corrected price differs from the VAT base, expect VAT and DST recomputation and an amended CAR.
Seller is a corporation; buyer is an individual (or vice versa): Corporate approvals (Board/Secretary’s Certificate) may be needed for the corrective instrument.
Price in foreign currency: The deed should state the peso equivalent as of a defined date (e.g., closing), and taxes are computed in PHP; a “wrong FX” is typically substantive, not clerical.
Installment sale: If the deed misstated total price or downpayment, fix both; attach the correct amortization schedule.
Movables/chattel mortgage: A price error in a chattel sale can be corrected similarly, but notify lenders so the SEC/LTO/Land Transportation Office (for vehicles) records are consistent.

Templates (you can adapt these)

1) Deed of Correction (Price)

DEED OF CORRECTION (Ref: Deed of Absolute Sale, Doc. No. ___; Page No. ___; Book No. ___; Series of ___)

KNOW ALL MEN BY THESE PRESENTS: …[parties and capacities, same as original]… WHEREAS, on [date], the parties executed a Deed of Absolute Sale covering [property description, TCT/Condo Cert. No., area, location]; WHEREAS, due to [clerical error/typographical mistake], Paragraph __ of said Deed misstated the purchase price; NOW, THEREFORE, the parties hereby CORRECT the Deed as follows: “The purchase price is ₱[amount in figures] ([AMOUNT IN WORDS] PESOS), Philippine currency.” All other terms and conditions remain unchanged. IN WITNESS WHEREOF… [Signatures of the same parties/spouses] [Notarial acknowledgment with ID details]

2) Parties’ Joint Affidavit (supporting proof)

JOINT AFFIDAVIT OF EXPLANATION We… state: (1) the true price agreed upon was ₱___; (2) the error arose because [explain]; (3) attached are [bank slip/receipt/reservation]; (4) we execute this to support tax and registration corrections.

Step-by-step checklist (copy-paste)

Identify the type of error (clerical vs. substantive vs. post-sale change).
Gather proof of the true price (receipts, bank records, pre-closing documents).
Draft and notarize a Deed of Correction/Supplemental Deed (same parties + spouses).
If BIR CAR not yet issued → file corrected set; pay recomputed CGT/CWT, DST.
If CAR already issued → request amended CAR; settle deficiency taxes/penalties if any.
Pay LGU transfer tax adjustments (if needed).
File with Registry of Deeds for annotation/registration.
Update secondary records: HOA/condo corp, tax declaration, utilities, lender.
Keep a closing file with all versions, receipts, and the money trail.

Bottom line

A wrong price in a Deed of Sale is fixable, but you must paper it properly and sync the correction with tax and registry records.
Use a Deed of Correction when the mistake is genuine and uncontested; go to court for reformation if there’s a dispute.
Expect more taxes if the corrected base is higher; expect more questions (and possibly donor’s tax issues) if it’s lower.
Avoid backdating or understating — the cleanest path is full, documented transparency.

If you want, paste the exact (anonymized) price clause from your deed and tell me what the real price and timeline were. I can draft a tailored Deed of Correction and a one-page BIR cover memo you can attach to your filing.