79 Days Left: What the BIR E-Invoicing Deadline Means for Your Business System

If your business issues invoices from a computerized system, sells online, or is classified as a large taxpayer, you have until December 31, 2026 to start issuing proper electronic invoices. That's 79 days from today. The BIR confirmed the deadline in a new circular last month, and the details make one thing clear: this is a data and systems project, not a paperwork one. Here's what changed, who's covered, and how I'd get a small Philippine business ready in time.

BIR E-Invoicing Readiness

The e-invoicing requirement itself isn't new. It comes from the Tax Code's electronic invoicing provision, and the BIR first set a March 14, 2026 deadline under RR No. 11-2025. In September 2025, RR No. 26-2025 pushed that to December 31, 2026 to give businesses time to reconfigure their systems.

What changed recently is Revenue Memorandum Circular No. 98-2026, issued on September 22, 2026. According to Grant Thornton Philippines' tax alert, it lays out the practical rules and keeps the December 31 deadline. Many owners had been holding off on spending until the guidance was clearer, and with the rules now out, coverage has spread fast. This week alone, local tax-tech startup Taxumo told Context.ph it's putting more resources into e-invoicing ahead of the deadline, and law firms have been publishing explainers on what counts as a valid e-invoice.

This is the part that surprises most of the small business owners I talk to. Under RMC 98-2026, invoices typed up in Word, Excel, Google Docs or Google Sheets don't qualify as electronic invoices, even if you email them. As Aureada Law explains, saving one of those as a PDF doesn't change anything. A valid e-invoice has to come from a registered or approved invoicing system, in a structured format whose data can be extracted and sent to the BIR. You can still hand the customer a printout, as long as the original was generated and issued electronically.

Think of it as the difference between a picture of an invoice and a record of one:

INVOICE_0457_final_v2.pdf

- Typed by hand into a spreadsheet template
- Number entered manually (can repeat or skip)
- Can be edited and re-saved after sending
- Totals are whatever the cell formula says
- Nothing the BIR's systems can read

{
  "invoice_no": "000457",
  "issued_at": "2026-12-15T10:42:00+08:00",
  "seller_tin": "XXX-XXX-XXX-00000",
  "buyer_name": "Sample Buyer Store",
  "lines": [{ "item": "Corn grits 50kg", "qty": 10, "unit_price": 1450.00 }],
  "vatable_sales": 12946.43, "vat": 1553.57, "total": 14500.00,
  "status": "ISSUED"
}
// Illustration only — not the BIR's official format

The bars show where each milestone falls between the first regulation and the deadline:

Based on Grant Thornton's summary of RMC 98-2026, the covered groups are:

• Businesses selling through e-commerce or internet transactions that are classified as small, medium or large taxpayers.
• Taxpayers under the Large Taxpayers Service, and those classified as large taxpayers under the Ease of Paying Taxes Act and RR No. 8-2024.
• Taxpayers using a Computerized Accounting System (CAS) or Computerized Books of Accounts with electronic invoicing, plus other invoicing software.
• Anyone else the BIR Commissioner later requires.

Micro taxpayers are exempt, though they can adopt e-invoicing voluntarily. Under RR 8-2024's classification, as summarized by PwC Philippines, "micro" means gross sales below ₱3 million a year and "small" starts at ₱3 million. So a sari-sari store with a paper receipt booklet probably isn't affected. A ₱5-million-a-year shop that takes orders through a website or online store, or a cooperative using a CAS-registered system, likely is. If you aren't sure where you fall, the BIR has a taxpayer classification inquiry function, and your RDO or accountant can confirm it.

From where I sit, building systems for small businesses and cooperatives in Bukidnon, the rules in RMC 98-2026 translate into a handful of concrete technical requirements:

You need a permit before your first e-invoice. Covered businesses must get a Permit to Issue (PTI) Electronic Invoice. An existing CAS approval doesn't replace it. According to Taxumo's breakdown, the BIR evaluates applications within 20 working days of receiving complete requirements. Then you have six months after the PTI to pass EIS certification, which checks that your system can extract and transmit sales data to BIR standards. Miss it and the PTI can be revoked.

Issued invoices are permanent. You can't delete, edit or overwrite an e-invoice once it's issued. A reduction needs a credit note that references the original, and an increase needs a new invoice. If your current system lets staff "just fix" an invoice, that has to change.

Branches and system changes matter. The head office and each branch need to be covered by a PTI. Branches on the same system share one, but a different system needs its own. Migrating to a new system, or changing its core details, requires a new or amended PTI. So if you plan to switch software, do it before you apply, not after.

You need a downtime plan. Brownouts and internet outages are real here. RMC 98-2026 says that during system or connectivity failures you issue a BIR-authorized manual invoice, then replace it with an e-invoice that references the manual number once you're back online. That means keeping an authorized backup booklet and a step in your system to record the replacement.

For developers, the lesson is that invoice data has to be append-only, sequential and exportable. Below is how I'd design that at the database level.

These are simplified examples from my own approach, written for PostgreSQL. They aren't the BIR's official schema. Your approved system and its EIS certification decide the actual format. But the principles carry over to any stack:

-- Illustrative invoice schema (NOT the BIR's official format)
CREATE TABLE invoices (
  id            BIGSERIAL PRIMARY KEY,
  branch_code   TEXT NOT NULL,              -- head office / branch
  invoice_no    TEXT NOT NULL,              -- sequential per branch
  issued_at     TIMESTAMPTZ NOT NULL DEFAULT now(),
  buyer_name    TEXT,
  buyer_tin     TEXT,
  vatable_sales NUMERIC(14,2) NOT NULL,
  vat_amount    NUMERIC(14,2) NOT NULL,
  total_amount  NUMERIC(14,2) NOT NULL,
  manual_ref_no TEXT,                       -- set when replacing a downtime manual invoice
  status        TEXT NOT NULL DEFAULT 'ISSUED',
  UNIQUE (branch_code, invoice_no)
);

-- Corrections never edit the original; they point to it
CREATE TABLE invoice_adjustments (
  id             BIGSERIAL PRIMARY KEY,
  invoice_id     BIGINT NOT NULL REFERENCES invoices(id),
  kind           TEXT NOT NULL CHECK (kind IN ('CREDIT_NOTE','ADDITIONAL_INVOICE')),
  amount         NUMERIC(14,2) NOT NULL,
  reason         TEXT NOT NULL,
  created_at     TIMESTAMPTZ NOT NULL DEFAULT now()
);

-- Block UPDATE and DELETE on issued invoices at the database level,
-- so no app bug or "quick fix" can change history.
CREATE OR REPLACE FUNCTION block_invoice_changes()
RETURNS trigger AS $$
BEGIN
  RAISE EXCEPTION 'Issued invoices cannot be changed. Create a credit note or a new invoice instead.';
END;
$$ LANGUAGE plpgsql;

CREATE TRIGGER invoices_no_update
  BEFORE UPDATE OR DELETE ON invoices
  FOR EACH ROW EXECUTE FUNCTION block_invoice_changes();

-- Give the app user INSERT/SELECT only
REVOKE UPDATE, DELETE ON invoices FROM app_user;
GRANT  INSERT, SELECT ON invoices TO app_user;

# E-invoicing readiness check (my working list)

[ ] Confirmed our taxpayer classification (micro / small / medium / large)
[ ] Confirmed whether we're covered (e-commerce, LTS/large, CAS/CBA user)
[ ] Chosen the system that will issue e-invoices (no more Excel/Word invoices)
[ ] System can export structured, machine-readable invoice data
[ ] Invoice numbers are sequential per branch and can't be reused
[ ] Issued invoices can't be edited or deleted; credit notes reference originals
[ ] Downtime procedure written: authorized manual invoice + later e-invoice replacement
[ ] PTI Electronic Invoice application filed (allow ~20 working days)
[ ] Plan and owner for EIS certification within 6 months of PTI
[ ] Staff trained; backups tested; customer data handled per RA 10173

With the year-end rush and the holidays coming, I'd treat mid-November as the real deadline for getting your PTI application in. Here's the order I'd follow:

E-Commerce

The Online Seller Above ₱3M

Website or online store orders, invoices made in a spreadsheet. Covered, and the spreadsheet has to go.

CAS User

The Co-op or Store With a CAS

Already registered, but CAS approval doesn't replace the PTI. Check if your vendor's system can export structured data.

Branches

The Business With Mixed Systems

Head office on one system, a branch on another. Each distinct system needs its own PTI, so consolidate first if you can.

If you're a cooperative, mill or shop in northern Bukidnon trying to get off spreadsheets before December, this is exactly the kind of work I do. See how I support businesses in Baungon and nearby towns, or browse all my services.

Sources: Grant Thornton Philippines (Sept 24, 2026); Taxumo (Sept 2026); Aureada Law (Oct 2026); KPMG (Oct 2025); PwC Philippines; Context.ph (Oct 13, 2026). This post is general information, not tax or legal advice.