Input VAT and output VAT: how the math actually works for VAT-registered businesses
VAT-registered businesses do not hand every peso of collected tax to the BIR. This plain-language guide explains output VAT, input VAT, and the credit mechanism in plain terms.
When a business registers for VAT, many owners assume it means collecting an extra 12 percent on every sale and remitting it all to the government. That is not quite right. VAT is structured as a chain tax: each business in the supply chain pays only on the value it added, not on the full selling price. Once you understand the two moving parts, the monthly or quarterly computation becomes much clearer.
The Two Sides of VAT
VAT has two halves, and both matter.
Output VAT is the tax you collect from your customers. Every time you issue a VAT invoice or official receipt, you add VAT on top of the selling price. That amount belongs to the government; you are holding it temporarily until you remit it at filing time.
Input VAT is the VAT you already paid when you bought goods or services for your business. When a VAT-registered supplier charges you VAT on a purchase, that becomes a tax credit you can use to reduce what you owe.
How the Computation Works
At filing time, the formula is simple:
Output VAT minus Input VAT equals VAT payable.
Say you collected 12,000 in output VAT from sales, and you paid 4,000 in input VAT to your suppliers. You remit 8,000 to the BIR. The 4,000 you already paid upstream offsets part of what you collected downstream.
If your input VAT is greater than your output VAT in a given period, you have an excess input tax credit. You carry it forward to the next period. Getting a cash refund requires a separate formal application and its own documentation process; the government does not automatically issue a refund.
What Makes Input VAT Valid
Not every purchase qualifies as creditable input VAT. Under the official BIR rules, three things need to be true:
- The purchase is related to your VAT-registered business activity.
- Your supplier is also VAT-registered.
- The VAT amount appears as a separate line on the invoice or official receipt, sometimes called a "VAT breakdown."
If a supplier is not VAT-registered, any amount they charge is not recoverable input VAT, regardless of what they label it. Always confirm your suppliers' VAT status before assuming you can credit their charges.
Common Mistakes to Avoid
Mixing personal and business expenses. Input VAT on purchases that are not for the business does not count. The BIR can disallow it during an audit.
Defective or missing invoices. An invoice without a separate VAT breakdown, or one from an unregistered seller, cannot support an input tax claim. Keep every valid VAT invoice organized, because the BIR can request them during an examination.
Treating carry-forward credits as cash. Excess input VAT rolls to the next period automatically. It does not become spendable money unless you file a formal refund or tax credit certificate application, which has its own rules and timeline.
Forgetting beginning inventory input tax. When you first register for VAT, the official rules allow a one-time claim on goods and assets already on hand at the point of registration. The conditions are specific, so verify them with the BIR or a tax professional before claiming.
The Simplest Way to Picture VAT
Think of VAT as a relay baton. Each business in the supply chain receives it from the buyer, keeps only its own portion, and passes the rest forward. By the time the product reaches the final consumer, the government has collected 12 percent of the final selling price, spread across every link in the chain.
Have a Specific VAT Question?
The rules around input and output VAT have details that vary by industry and transaction type. Type your question into AskOnward for an answer grounded in the official BIR rules, without having to dig through dense regulation on your own.
This article is for general information and is not affiliated with the government. For official forms and the latest rules, see the Bureau of Internal Revenue at bir.gov.ph.