A lot of shop owners who import through formal channels never think about input invoices. The goods arrive, customs is cleared, and that feels like done. The problem usually shows up later: a tax audit, a bank asking for inventory documentation, or a landed cost that was wrong from the start because one layer of charges was never counted.
What input invoices mean in an import context
When goods come through formal import (chinh ngach), they cross an official border checkpoint, go through customs declaration, and trigger two tax payments: import duty and import VAT. After clearance, the customs authority issues a set of documents. The customs declaration form and the tax payment receipts are the input documents that accountants and tax authorities use to confirm the origin of goods and the taxes already paid.
The customs declaration and the import VAT receipt are the formal import equivalent of a domestic VAT invoice. They play the same role that a red invoice (hoa don do) plays when you buy from a domestic registered supplier, but they look different and come from a different source.
This matters because the documentation chain starts here. If these papers are lost or never requested from your freight agent, the entire downstream record is gone.
Who actually needs to pay attention
Not every seller faces the same obligations, but it is wrong to assume that small scale means no exposure.
Household businesses on a flat-rate tax (ho khoan). This group pays tax at a set rate based on declared revenue rather than itemizing invoices. If you are here, keeping the customs declaration is still important as proof of goods origin during a physical audit, even though you do not need it to claim a VAT deduction.
Household businesses and companies on the VAT deduction method (khau tru VAT). This is the group with the most at stake. The VAT paid at the border (shown on the customs tax receipt) is input tax that can be offset against the output VAT you collect from customers. Without the documentation, you lose that offset and effectively pay the same tax twice.
Companies with audits or bank loans. This is where missing import records cause the most immediate damage. Banks and auditors both ask for documentation that supports the value of inventory on the books. The customs declaration is that documentation. Without it, inventory cannot be substantiated, and financing conversations get complicated.
How import VAT is calculated and what it does to landed cost
Two main charges come due at the border when goods from 1688 arrive through formal channels.
Import duty. The rate depends on the HS code for each product category. Many common consumer goods from China carry import duty rates that vary widely: some categories are 0%, others run 20 to 30%. You need to look up the correct HS code for what you are importing to find the actual rate. Duty is calculated on the customs value (CIF): the goods price plus freight plus insurance.
Import VAT. After import duty is calculated, VAT is applied to the sum of (customs value plus import duty). The standard import VAT rate for most general goods is 10%, though some categories are lower. This is separate from domestic VAT that shows up on sales.
A simple example makes the impact concrete. Suppose a shipment has a CIF customs value of VND 10 million. Import duty at 10% adds VND 1 million. Import VAT at 10% applies to the VND 11 million total, adding another VND 1.1 million. Total border taxes: VND 2.1 million.
If you qualify for VAT deduction and keep the right records, the VND 1.1 million VAT piece comes back when you file your periodic return. If you do not, the full VND 2.1 million is a real cost that belongs in landed cost. Either way, the goods cost more than the 1688 price plus freight, and the gap is not trivial.
Why many sellers skip this and what happens later
Several patterns explain why input documentation gets ignored.
No one explains it. The freight company or customs agent hands over a bundle of papers when the shipment clears. If you have no guide for reading that bundle, the customs declaration and tax receipts get filed in a drawer and forgotten.
Small operations without an accountant. Early on, when volume is low, many owners track finances the simple way: add up the goods cost and shipping, whatever is left is profit. Invoices and tax records do not appear in that mental model.
The assumption that small operations go unnoticed. The threshold for scrutiny is not purely about scale. E-commerce platform revenue is increasingly cross-referenced against reported income at the tax authority level. A large gap between reported revenue and documented costs is a flag that can trigger a review at any size.
The most common consequence is not an immediate fine. It is a back-tax assessment with penalties during a retrospective audit. Or it is losing the right to claim the input VAT deduction because documentation is missing, which means paying VAT on the same goods twice. For shops that import regularly at decent volume, that is a material number.
Keeping the right records
After each formal import shipment, the documents you need to retain typically include:
- The customs import declaration (with the customs authority's clearance stamp)
- The import duty and import VAT payment receipts
- The commercial invoice from the Chinese supplier
- The bill of lading or airway bill
- The packing list
For standard consumer goods, nothing more complicated than this is required. But these specific documents need to be kept for at least 5 years under standard accounting document retention rules.
If you work with a freight forwarder or customs broker, ask them to hand over the full document package after every shipment, not just a confirmation that "the goods have arrived." Most reputable operators have a standard process for this. They simply will not send unless asked.
The real impact on landed cost and pricing
A concrete example to see how the numbers shift: suppose you import an item priced at 50 yuan on 1688. At around 3,600 VND per yuan (check this when you calculate, it moves), that is roughly VND 180,000 in goods cost. Add domestic China freight and the ocean or road freight leg to Vietnam, say VND 20,000 per unit, bringing CIF to roughly VND 200,000.
If import duty for this product category is 15%, add VND 30,000. Import VAT at 10% on the VND 230,000 base adds VND 23,000. Border taxes total: VND 53,000 per unit.
If you are on a flat-rate tax scheme or otherwise cannot claim a VAT deduction, your real landed cost is close to VND 253,000 per unit, not VND 180,000. Pricing off VND 180,000 means every margin calculation is wrong from the first step.
If you can claim the VAT deduction and keep proper records, the VND 23,000 VAT portion is recoverable, bringing real landed cost to roughly VND 230,000. Still significantly higher than goods cost plus basic freight. Any pricing model that does not include border taxes will produce a margin number that is too optimistic and may result in selling at a loss in practice.
When to bring in an accountant or tax advisor
Not everyone needs a professional accountant from day one. But there are specific points where going it alone costs more than asking for help.
When your imports run at consistent volume (several hundred million VND per shipment or more), when you are moving from informal selling to registering a household business, or when the platform requires tax documentation to continue selling, those are the moments to sit down with someone who knows e-commerce and import tax. A single consultation often surfaces charges that were being left out of cost calculations or mis-categorized in ways that quietly erode margin every cycle.
Bottom line
Input documentation from formal imports is not a formality for large companies. It is the foundation for accurate landed cost, the basis for claiming back import VAT if you qualify, and the paper trail that protects you when someone asks where the goods came from. Keeping the full document set from every shipment is one of the easiest steps in the entire import process, and the one most commonly skipped until it is too expensive to fix.