We assess the applicable scheme, organise sales records and prepare quarterly OSS or monthly IOSS returns using marketplace and payment data.
An online seller came to ARG with OSS and IOSS records and deadlines spread across several people. ARG established what had already been completed, identified what was missing and coordinated the remaining responsibilities.
The client found ARG’s communication particularly useful because it explained the actual work ahead instead of leaving the team to interpret general guidance. That practical issue is common in cross-border online sales, where domestic Bulgarian VAT reporting, Union OSS and IOSS can involve different transaction and shipment data.
ARG can help when you need to
Identify the buyer, seller, stock location and dispatch route; B2B, domestic and imported sales need different treatment.
Check establishment, VAT identifiers, prior participation and any required IOSS intermediary before the first eligible sale.
Check the EUR 10, 000 rule where available; IOSS needs eligible non-excise consignments with intrinsic value no more than EUR 150.
Keep order-level electronic evidence, ten-year records and authority to submit returns and pay by the scheme deadline.
OSS, the One Stop Shop, is an optional way to report qualifying consumer sales across EU VAT jurisdictions through one Member State. IOSS is its import scheme for eligible goods dispatched from outside the EU in consignments with intrinsic value no more than EUR 150, excluding excise goods. A distance sale means the supplier arranges or participates in transporting goods to the consumer across the relevant border. It is not simply any sale made online. The European Commission explains the three schemes and their definitions: Union OSS, non-Union OSS for eligible services supplied by non-EU businesses, and IOSS for qualifying imports.
Before choosing a scheme, test whether destination VAT applies. Under Article 59c of the VAT Directive, the EUR 10, 000 annual threshold combines qualifying cross-border consumer telecommunications, broadcasting and electronic services with intra-EU distance sales dispatched from the supplier’s sole Member State of establishment. It must not be exceeded in either the current or preceding calendar year. This is one EU-wide total, not an allowance per country. Other services, imported goods and business structures established in more than one state do not obtain this threshold merely because sales are small. A qualifying supplier can elect destination treatment, normally binding for two calendar years.
It also matters because OSS and IOSS are not a general replacement for all VAT work. They sit beside the ordinary Bulgarian VAT return. If a supply is domestic to Bulgaria, or otherwise belongs in Bulgaria’s normal VAT reporting, it does not move into OSS just because the seller also uses an e-commerce platform. The correct route depends on the nature of the supply, the customer type and the place of taxation.
For this service, the real first step is to map the transactions before the filing calendar becomes a problem. ARG would be looking for three things.
That is why this work has commercial value even before a return is filed. A seller can have correct bookkeeping and still choose the wrong reporting path if the platform data, fulfilment chain or customer location is not analysed first. In practical terms, the wrong route can create duplicate filings, missing filings, or mismatches between the VAT return and the sales records.
The filing route must follow the supply, not the convenience of the spreadsheet.
If you are already selling through marketplaces, using multiple warehouses, or invoicing customers in several EU states, this service is usually relevant before the first return is prepared. If the business only makes ordinary domestic Bulgarian sales, OSS or IOSS support may not be the right service at all, because the issue is standard VAT compliance rather than special e-commerce reporting.
Article 369b defines Union OSS eligibility. It includes intra-EU distance sales of goods and eligible consumer services taxable in a Member State where the supplier is not established. An ordinary Bulgarian seller’s domestic sales generally remain in domestic reporting. There are specific exceptions: a marketplace treated as a deemed supplier can report certain domestic goods sales in Union OSS. Deemed supplier means the platform is treated as buying and reselling the goods for VAT under Article 14a even though the commercial seller owns the stock. Obtain the platform’s transaction classification before assuming that its VAT collection removes your own reporting obligations.
In practical terms, OSS is for sales where the VAT destination is another EU country and the scheme is the authorised way to report that destination VAT through one filing. For a Bulgaria-based business, that usually means:
The point of OSS is not to change the tax result. It changes the reporting channel. The Member State of identification receives the return, splits it by Member State of consumption, and forwards the data and the VAT due onward. That is why transaction mapping is essential. The seller must know where the customer is, what the supply is, and whether the supply belongs in OSS or in a local domestic return.
A domestic Bulgarian supply remains in the Bulgarian VAT return. A sale made in Bulgaria to a Bulgarian consumer, where the supply is domestic for VAT purposes, does not become an OSS item just because the customer ordered online. The same is true where the supply does not meet the OSS conditions for the relevant scheme. The special regime is a reporting simplification, not a universal online-sales wrapper.
For example, goods sent from your Bulgarian warehouse to a consumer in France may be a Union OSS sale once destination taxation applies. Goods sent from China directly to that customer require an import analysis instead. Goods already stored in a French fulfilment centre are not IOSS imports when later sold from that stock. A sale from the French warehouse to a French consumer by an ordinary seller can create French domestic obligations, while a shipment from that warehouse to Germany may enter Union OSS. Your stock movements and acquisitions can still require foreign registration even when the final cross-border consumer sale is reported through Bulgaria.
For a business, the immediate consequence is record design. Sales systems, checkout settings, VAT codes and invoice logic must distinguish the destination sale from the domestic one. If that split is not built into the workflow, the return may be technically filed on time but still be wrong in substance. That is the kind of error OSS support is meant to prevent.
For Bulgaria-based sellers, this also means that a clean VAT process usually has two layers. One layer handles the regular Bulgarian VAT return. The other handles the OSS return for the eligible cross-border B2C turnover. Keeping those layers separate is what allows the business to file correctly without overreporting domestic supplies or leaving cross-border sales outside the special scheme.
Tell us where you live, how your business works and what you want to change. We will help you identify the questions to resolve and the next steps to consider.
Registration follows the seller’s establishment and the chosen scheme. For Union OSS, a business established in Bulgaria normally identifies here; a non-EU business with no EU establishment can use Union OSS for qualifying goods and identifies where dispatch starts, subject to rules when several states are involved. Non-Union OSS is for businesses with neither their business establishment nor a fixed establishment in the EU and covers eligible consumer services. A VAT number alone is not a fixed establishment. Provide incorporation details, operating locations, staff and technical resources, warehouses, VAT registrations and any previous scheme participation before selecting Bulgaria.
ARG would normally check the client’s establishment position, the business model, the scheme choice and the transaction flow before the application is sent. That matters because the registration is not just a formality. It determines which scheme the business is allowed to use and from when. If the file is incomplete, the authority can refuse it with reasons, which creates a timing problem before the first filing deadline.
The registration file should identify the actual legal seller, relevant VAT number, establishments, websites and contacts, intended first transaction date and any IOSS intermediary. Check that electronic filing authority covers the correct National Revenue Agency service. The authority checks eligibility and previous registrations or exclusion periods; the existence of a Bulgarian accountant or correspondence address does not itself make Bulgaria the correct state. Keep the application acknowledgement and the registration decision with the sales-launch records. A pending application should not be treated as an active IOSS number for customs clearance. The Commission’s registration guidance explains these checks and identifier rules.
Union and non-Union OSS normally start on the first day of the next calendar quarter. An earlier first eligible supply can be covered if the business notifies its Member State of identification by the tenth day of the following month. IOSS follows a different rule: participation begins when the individual IOSS VAT identification number is allocated. Do not apply the quarterly start rule to imported parcels. Record the first eligible transaction and notification date, confirm the accepted effective date, and separately identify earlier sales needing ordinary destination-country reporting.
In practice, this means the business should not wait until the quarter is almost over before checking the filing route. If the first cross-border sale has already happened, the date of that first delivery may become the trigger for the effective date, but only if the application is lodged in time. If the application misses that window, the business may have to report the earlier turnover through another route and the return workflow becomes more complicated.
A concise way to think about the file is this.
For a client, the commercial decision is whether to register before launch, at the first sale, or only once the cross-border volume justifies the special workflow. ARG’s role in this stage is to tie the registration file to the actual sales data, because the right answer depends on what is being sold, where the customer is, and whether Bulgaria is the correct Member State of identification.
IOSS applies to distance sales of goods imported from third territories or third countries, and the Commission states that the scheme is limited to consignments with a value of up to EUR 150 per consignment.European Commission The important point is that the threshold is tied to the individual consignment, so the product value, shipment structure and customs data all have to line up before the business treats a sale as IOSS-eligible.
The threshold is not a general monthly sales cap. It is a per-consignment limit. That means the seller, fulfilment provider and customs documentation must all point to the same shipment value. If the merchandise is bundled, split or re-invoiced in a way that changes the customs picture, the IOSS analysis can change with it. For an online seller, that makes product classification and logistics a compliance issue, not just an operational detail.
The schemes follow different transaction flows. Union OSS can cover an intra-EU distance sale, while IOSS requires the goods to be dispatched from outside the EU for that consumer sale. Non-Union OSS concerns eligible services supplied by a business without an EU establishment. A company can use more than one scheme where it meets each set of conditions, but one sale must not be reported twice. Use a separate VAT code for each flow and document why the code applies before importing platform data into the return.
The Commission states that excise goods cannot be declared in the import scheme.European Commission That exclusion matters because it means the seller cannot assume that every low-value imported item fits IOSS just because the consignment is under EUR 150. The goods themselves must also be eligible.
A practical example helps. If a non-EU marketplace seller sends a low-value parcel of ordinary consumer goods to an EU private customer, IOSS may be available if the other scheme conditions are met. If the parcel contains excise goods, the import scheme is not available even if the consignment value is below the threshold.
For this service, the real risk is a mismatch between the commercial order and the customs record. ARG would normally check the item description, shipment value, seller chain and the platform data before deciding whether IOSS is available. If the threshold is exceeded, or the goods fall into an excluded category, the business should not force the shipment into IOSS. It must use the correct customs and VAT route instead.
That is why product review is part of the filing work. A correct IOSS return starts with a correct shipment decision, not with the form itself.
Article 63c of Implementing Regulation 282/2011 specifies the electronic records behind special-scheme reporting. These include the state of consumption, description and date of supply, taxable amount and currency, VAT rate and amount, payments and advances, and information supporting the customer’s location; goods records also need the relevant dispatch and return information. Keep these records for ten years from the end of the transaction year, including after leaving the scheme. An order summary or a saved return PDF does not reproduce the evidence needed to check the calculation.
Union and non-Union OSS returns are quarterly; IOSS returns are monthly. Filing and payment are due by the end of the following month, and a registered participant files a nil return when the period has no reportable supplies or corrections. For example, the second-quarter OSS deadline is 31 July; June IOSS has the same deadline but covers only that month. The special return remains separate from Bulgaria’s ordinary monthly VAT return. Schedule the platform export and review early enough for the tax payment to arrive by the deadline, including where the deadline falls at a weekend.
The Member State of identification, here Bulgaria, receives the return, splits it by Member State of consumption and then forwards the data onward. The taxable person pays the VAT due to Bulgaria, and Bulgaria distributes the amounts to the relevant Member States.European Commission That structure means the return has to be accurate at the source. If the sales data are wrong, the error travels through the whole payment chain.
For IOSS, the date of payment acceptance matters as well as dispatch. Article 369o of the VAT Directive treats the supply as occurring when payment is accepted. Keep the payment confirmation or authorisation event with the order and distinguish it from the later platform payout into the business bank account. A payout made next month does not automatically move the sale into that month’s IOSS return. Where a payment is cancelled, refunded or disputed, preserve the event history so the accountant can identify whether the original sale, a correction or an unresolved receivable remains.
A compliant workflow usually needs a record split at least across these points.
The safest compliance file is the one that lets the return be rebuilt without guesswork.
For a client, the next decision is not only whether to file on time. It is whether the sales, customs and accounting teams are all using the same source data before the deadline arrives. ARG can coordinate that responsibility split so the return, the records and the payment trail all point to the same transactions, which is the practical safeguard against both penalties and avoidable corrections.
A non-EU seller normally needs an EU-established intermediary for IOSS. The narrow mutual-assistance exception depends on both the seller’s country and the country from which goods are dispatched; the Commission illustrates it with qualifying Norwegian sellers shipping from Norway. It does not automatically cover that seller’s goods sent from China. The intermediary takes responsibility for scheme obligations in the represented seller’s name and receives a separate IOSS number for each seller. It is a defined tax role, not simply the courier, customs representative or external bookkeeper. Confirm the appointment before promising customers IOSS treatment at checkout.
An EU-established seller may use IOSS directly if it meets the conditions or choose an intermediary. If the business uses a marketplace, establish whether the platform is the deemed supplier for that particular imported sale and whose IOSS number belongs in the customs process. Never assume one account-level setting answers every transaction. A marketplace can treat imports, warehouse sales and business-customer sales differently. Retain its transaction reports and tax statements, reconcile them to orders and check any sales made through your own website separately. Do not report a platform’s deemed supply again as your own identical taxable consumer sale.
Import VAT and customs duty are separate charges. Regulation 2026/382 removed the former low-value customs-duty relief from 1 July 2026 and introduced temporary duty arrangements. The IOSS consignment limit continues to concern the import VAT scheme; it is not a promise of duty-free delivery. Ask the customs declarant to confirm the tariff classification, available exception and current duty calculation, then agree who bears that cost under your sales and delivery terms. The checkout description, carrier invoice and accounting entries should separate VAT, customs duty and the carrier’s own service charges.
Goods already stored within the EU do not qualify for IOSS on their later sale merely because they originally came from China or another third country. The relevant question is whether the consumer transaction involves dispatch from outside the EU. For inventory imported in bulk and then sold from a European warehouse, keep the original import entry separate from subsequent sales and stock transfers. If your fulfilment provider changes the dispatch location automatically, obtain a report of the actual country used for each order instead of relying on the customer-facing delivery estimate.
In practice, the business should ask three questions before using IOSS.
If any one of those answers is no, the import scheme is not the right filing route.
Articles 369j and 369w keep input VAT outside the special OSS and IOSS return. Do not subtract advertising, fulfilment or purchase VAT from the destination VAT being declared through the scheme. Recovery is considered through the applicable domestic return or cross-border refund procedure, depending on the country, the supplier’s other registration obligations and the normal deduction conditions. Maintain separate expense evidence and check the legal entity named on each invoice. A platform payout after fees is not a substitute for reporting the correct taxable sale and separately recording the platform expense.
For a multi-channel seller, use a transaction matrix with the seller, platform role, stock country, dispatch country, destination, buyer status and scheme. For example, your own Bulgarian stock sent to Germany, a marketplace’s deemed import sale and an ordinary Bulgarian domestic order can appear together in a payout. They still require different VAT treatment. Reconcile the matrix to gross order values, refunds, commissions, reserves and bank receipts. Explain each difference rather than forcing the return total to equal the amount that the platform happened to transfer during the quarter.
A useful client takeaway is this. If the product catalogue is changing frequently, or if the business uses several suppliers and shipping routes, the IOSS decision should be reviewed before the first shipment goes live. Otherwise the return logic can become an after-the-fact correction exercise instead of a controlled filing process.
An already-submitted OSS or IOSS return is normally corrected through a subsequent return for periods beginning from 1 July 2021. Identify the original consumption state, period and correction amount, retaining the refunded order or other supporting evidence. The scheme generally allows corrections within three years of the original filing deadline. After that, any permitted correction is handled directly under the affected state’s rules. This is different from replacing a Bulgarian domestic VAT return before its filing deadline, so the accountant needs to know which return actually contains the error.
A customer return after quarter-end therefore needs two linked records: the original sale and the later refund or price adjustment. Keep the order reference, original VAT rate and consumption state, refund date and reason. Do not apply today’s VAT rate automatically to an older transaction. Where the customer keeps part of a bundle or pays a cancellation charge, examine the actual revised consideration instead of reversing the whole original order. The export should show the correction separately so that its treatment can be reviewed before submission.
Payment must identify the particular special-scheme return using its unique reference and reach the designated account by the deadline. The Member State of identification distributes the tax to consumption states. A payment to the ordinary Bulgarian VAT account or with the wrong reference may not settle the intended OSS liability. Save the accepted return, reference, bank instruction and evidence of receipt or account allocation. If the portal balance does not agree with your calculation, resolve the difference before assuming the filing is fully complete.
Destination-country treatment also means that product rates need evidence. Classify the actual product or service and retain the basis for the rate used in each consumption state. Do not copy the Bulgarian standard rate across the entire EU, or assume that a product description on a marketplace proves eligibility for a reduced rate elsewhere. A catalogue update, subscription change or combination of goods and services can require a fresh classification. Maintain an approved rate table with effective dates so later refunds and corrections can be traced back to the original sale.
A usable compliance file should let the accountant or adviser reconstruct the return without relying on memory. It should show the customer type, destination, supply category, quarter, VAT rate used, and the documents that support the treatment. Where IOSS is involved, the shipment and customs data should also be retained in the same working logic.
The most common failure point is not the law. It is the handoff between sales, logistics and accounting. If one team closes the month without the shipment data, another team may file the return on incomplete numbers, and a third team may discover the gap only after the deadline. That is exactly the situation where ARG’s coordination work has practical value.
The useful next step is to assign one owner for the source data, one reviewer for the scheme classification and one final checker for the filing and payment trail. If those responsibilities are not fixed, the business can still end up with late filings or unusable records even when the underlying sales are legitimate. That is the point where a small filing problem becomes a wider compliance issue.
The EU small-enterprise exemption and Union OSS can interact: eligible SME participation does not automatically prevent Union OSS, but the business still needs the relevant national VAT identifier and must distinguish exempt from taxable destination sales. The Commission states that an SME participant must opt out of that exemption to use IOSS. Do not confuse the SME framework with the separate EUR 10, 000 place-of-supply threshold. Provide the SME authorisation, countries covered, turnover calculations and identifier before deciding which consumer sales belong in a taxable special-scheme return.
If a return or payment is late, first identify the missing period, original deadline, accepted submissions and actual account allocation. Prepare the missing return using the underlying order data and pay through the correct reference. Review reminders from both the identification state and the consumption states, because recovery action and interest or penalties can arise in the state owed the tax. Repeated failures can lead to exclusion from the scheme. Keep a written response log and fix the data or approval delay that caused the missed filing rather than simply carrying the turnover into a later period.
That is especially relevant for online sellers with recurring month-end sales spikes. If the sales system, the warehouse data and the bookkeeping close on different schedules, the quarter-end return can be filed with missing numbers or after avoidable delay. ARG’s role is to align those schedules so the quarter can close on a defensible set of figures rather than on estimates.
Electronic records must be available to the relevant tax authorities without delay on request. Preserve exportable source data as well as readable supporting documents; access to a live marketplace dashboard alone may disappear when an account closes. Agree how transaction IDs, invoices, payment events and shipping records are linked and who can retrieve them. Store the mapping used for each filed period with the final output. A ten-year retention obligation applies even if you change accountants, move to another platform or stop using the scheme.
For a client, the practical standard is simple. The records should let the business answer these questions without guesswork.
A useful service outcome is responsibility mapping. In a cross-border online sales setup, one person may know the platform data, another the customs flow, and another the accounting ledger. If nobody owns the final classification, the filing is vulnerable even when each team has done part of the job correctly. ARG can coordinate that split so the business knows who supplies the source data, who reviews the scheme fit and who confirms the final submission.
That coordination has a direct practical effect. It reduces the chance of a late return, an incomplete e-register and a mismatch between the quarterly filing and the underlying transactions. It also makes it easier to decide whether a transaction belongs in OSS, in IOSS or in the ordinary Bulgarian VAT return before the deadline arrives.
The real implication for the client is that OSS and IOSS support is most valuable when it is used as a control function, not as a last-minute filing fix. If the business wants to avoid repeated corrections, the next step is to build the filing calendar and the record owner map before the next quarter closes.
Compare the related procedures in this category, including their requirements and the stage at which you need them.
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