Cross-border tax planning usually shows up on a founder’s radar in one of two moments: either a European company is restructuring to raise from U.S. venture capital, or a U.S. company is landing its first customers and employees in Europe. Both situations trigger real tax consequences on both sides of the Atlantic, and both are far easier to get right at the start than to fix after a term sheet is signed or a European subsidiary is already operating.

This article covers both directions: what happens tax-wise when a European startup flips to Delaware to raise U.S. capital, and what a U.S. company needs to plan for once it starts operating in Europe.

Two Directions, Two Tax Problems

It’s worth separating these upfront because founders often conflate them. A “flip” is about a non-U.S. company restructuring so a Delaware entity becomes the parent, typically to satisfy U.S. investors’ expectations around cap table structure and governance. Expanding a U.S. company into Europe is the reverse flow: a Delaware C-Corp adding operations, employees, or subsidiaries abroad. The tax questions, and the paperwork, are different for each.

The Delaware Flip: Why It Happens and What It Triggers

Most U.S. venture funds are structured to invest in Delaware C-Corps, and many simply won’t lead a round into a foreign holding company, for governance, tax, and fund-structuring reasons of their own. That’s what drives the common “Delaware flip”: the founders and existing shareholders of a foreign operating company exchange their shares for shares in a newly formed Delaware corporation, which becomes the new parent, with the original company continuing to operate as its foreign subsidiary.

Once that flip happens, the foreign operating company typically becomes a Controlled Foreign Corporation (CFC) for U.S. tax purposes, and that status brings real, recurring obligations. The Delaware parent’s U.S. shareholders generally have to include their share of the CFC’s income under the GILTI regime (Global Intangible Low-Taxed Income) each year, even if no cash is actually distributed, and certain categories of passive or related-party income may also be taxed currently under Subpart F rules, independent of GILTI. On top of the tax itself, the company must file Form 5471 annually for each foreign subsidiary, a form with a strict, brutal penalty regime: a minimum $10,000 penalty per form for late or incomplete filing, per year, regardless of whether any tax was actually owed.

There are ways to manage the GILTI hit, including a Section 962 election that lets individual U.S. shareholders be taxed at corporate rates on their GILTI inclusion, which can meaningfully reduce the effective rate compared to ordinary individual tax rates. None of this is a reason to avoid flipping, U.S. investors will often insist on it regardless, but it’s a reason to bring in tax advice before the flip closes, not after the first Form 5471 deadline is missed.

Expanding a U.S. Company Into Europe: The Permanent Establishment Question

Going the other direction, a U.S. company that starts hiring or operating in Europe has to watch for permanent establishment (PE): the risk that a European tax authority decides the company has enough of a taxable presence in its country to claim a share of the profits attributable to that activity, even without a formally registered local entity. A dependent agent who regularly negotiates or closes contracts on the company’s behalf, or a fixed place of business used for core operations, can be enough to trigger PE in some countries. With remote work now common, this risk shows up in unexpected places: a key employee who relocates to Spain or Portugal and keeps working for the U.S. parent can, in some circumstances, create exactly this kind of exposure.

VAT: The Tax That Doesn’t Exist Back Home

Value-added tax is probably the single biggest adjustment for a U.S. company selling into Europe, simply because nothing quite like it exists domestically. VAT applies to the sale of goods and most services within the EU, and a U.S. company selling digital services or goods directly to European consumers generally needs to register and collect VAT, even without a physical presence there. The EU’s non-union OSS (One Stop Shop) scheme simplifies this considerably: a single VAT registration in one EU member state lets a non-EU company report and remit VAT owed across all EU countries where it has consumer sales, instead of registering separately in each one.

Transfer Pricing: Keeping Intercompany Deals Defensible

Once a U.S. parent and a European subsidiary (or vice versa) start exchanging services, licensing IP, or lending money to each other, transfer pricing rules apply on both sides. Section 482 of the U.S. tax code requires related-party transactions to be priced as if the parties were unrelated, and requires contemporaneous documentation to support that pricing and avoid penalties in an IRS audit. European tax authorities apply the same arm’s length principle, generally following OECD guidelines, and increasingly share information with U.S. authorities to check that the numbers match on both sides of a transaction. Documenting these intercompany arrangements properly from the first dollar of intercompany billing, rather than retrofitting documentation years later, is one of the cheapest insurance policies a growing company can buy.

Tax Treaties: Preventing the Same Dollar From Being Taxed Twice

The United States maintains bilateral tax treaties with the large majority of EU member states, and these treaties are what actually make cross-border structures workable: they set reduced withholding tax rates on dividends, interest, and royalties flowing between the U.S. and the treaty partner, and they generally include tie-breaker rules to resolve cases where both countries might otherwise claim the same income. A separate mechanism, the Foreign-Derived Intangible Income (FDII) deduction, gives U.S. C-Corps a lower effective tax rate on income earned from foreign use of their intellectual property or services, which is a meaningful factor in deciding where to hold IP within a group. None of these tools apply automatically; they require the corporate structure and the underlying agreements to actually satisfy each treaty’s conditions.

State-Level Considerations Founders Forget

Cross-border tax planning tends to focus on the federal and EU layers and skip over U.S. state-level obligations that apply regardless of where else the company operates. A Delaware C-Corp still owes Delaware’s annual franchise tax and report, calculated on a formula tied to authorized shares that can produce a surprisingly large bill if not managed with the alternative assumed-par-value method. Separately, any company selling into U.S. states, including a European company selling to American customers, needs to track economic nexus thresholds for sales tax, a rule that expanded dramatically after the Supreme Court’s 2018 Wayfair decision: crossing a state’s sales or transaction threshold can create a sales tax collection obligation even without any physical presence in that state.

How Delvy Helps

At Delvy, we work with founders and investors on both sides of this equation: structuring the Delaware flip so U.S. investors get the entity they expect while the founding team understands exactly what GILTI, Subpart F, and Form 5471 will mean going forward, and helping U.S. companies expanding into Europe manage permanent establishment risk, VAT registration, and transfer pricing documentation as they grow. Our position spanning both tax systems means these two conversations happen with one advisor, not two disconnected ones.

If your company is navigating a flip, a European expansion, or both at once, let’s talk through what your structure actually requires.