Two Systems Built on Different Assumptions

Founders often describe FDA clearance and CE marking as the same task done twice. They differ in who reviews the file, what evidence convinces that reviewer, when the quality system has to exist, and what happens after launch. Treating them as one project with two output formats is a reliable way to blow a device budget.

The core difference is structural. In the US a government agency reviews your device before it goes on the market and issues a decision on that specific product. In the EU a private conformity assessment body, called a Notified Body, audits your quality system and reviews your technical documentation against the regulation, after which you affix the CE mark yourself. Nobody in Europe issues an approval letter the way FDA does.

Classification Comes First, and the Two Systems Disagree

Everything downstream depends on classification, so establish it in both jurisdictions before planning anything. The threshold question of whether you are regulated at all is worth settling first using the test in is my product a medical device.

The US uses three classes, and the practical work is finding your product code and regulation number in the FDA classification database. That entry tells you the class and the required pathway directly. The class structure and what each one demands is laid out in FDA medical device classes.

The EU uses four: I, IIa, IIb, and III, assigned by applying classification rules based on invasiveness, duration of contact, energy delivery, and software function. The rules produce different answers than the US database does. Software that drives clinical decisions frequently lands at IIa or higher in Europe while being a Class II 510(k) product in the US. The consequence is immediate: a Class I product in Europe can be self-declared with no Notified Body involvement, while Class IIa and above cannot.

What the Reviewer Wants to See

The US system is comparative for most products. A 510(k) argues that your device is substantially equivalent to a legally marketed predicate in intended use and technological characteristics, and the quality of your predicate selection largely determines the outcome. The mechanics are covered in the 510(k) submission process. When no predicate exists but the risk is low or moderate, the De Novo pathway creates a new classification. High-risk devices go through premarket approval with clinical data.

The EU system is absolute. There is no predicate concept. You demonstrate conformity with the General Safety and Performance Requirements and support it with a clinical evaluation that establishes your device's own benefit-risk profile. Under the current Medical Device Regulation, leaning on published literature about similar devices is far harder than it once was, because you must demonstrate technical, biological, and clinical equivalence to a specific device and typically prove you have contractual access to that device's technical documentation. In practice most IIa and above devices now need their own clinical data. That change alone has pushed many European submissions past the cost of the equivalent US clearance, and it is the single biggest shift described in EU MDR explained.

When the Quality System Has to Be Real

This is the timing difference that surprises people most.

For a US 510(k), FDA does not audit your quality system before clearance. You must comply with the Quality System Regulation, and an inspection can come later, but the submission itself is a technical file. Many companies clear a device with a quality system that is documented but lightly exercised, then mature it before launch.

For CE marking above Class I, a certified quality system is a precondition. Your Notified Body audits it, and the certificate to ISO 13485 generally has to be in place before or alongside the technical documentation review. That means building the full system, running internal audits, closing findings, and holding a management review before you can even schedule the device review. Add six to twelve months if you are starting from nothing.

Timelines and Money

Realistic ranges for a moderate-risk device, assuming the engineering and testing are already done.

  • US 510(k). FDA's review clock targets 90 days, but the calendar time from submission to clearance averages closer to five to eight months once additional information requests are counted. Agency user fees plus consulting and submission preparation commonly total 40,000 to 150,000 dollars, on top of testing.
  • US De Novo. Twelve to eighteen months is typical, with substantially higher preparation cost and usually some clinical evidence.
  • EU CE mark, Class IIa or IIb. Twelve to twenty-four months is the current reality, driven less by review effort than by Notified Body capacity. Getting a signed contract with a Notified Body can itself take three to six months, and small companies with unusual devices are sometimes declined. Fees to the Notified Body alone often run 40,000 to 120,000 dollars, with annual surveillance audits after that.

Both figures sit inside a much larger development budget. The full picture, including biocompatibility, electrical safety, usability, and verification testing, is broken down in how much FDA approval costs for a medical device.

What Europe Requires That the US Does Not

Even after the mark is affixed, the EU imposes obligations with no direct US equivalent. You need an Authorized Representative established in the EU if you have no legal presence there, and that representative carries real liability. You need a designated Person Responsible for Regulatory Compliance. You register in the European database and generate a Basic UDI-DI. You maintain a post-market surveillance plan, produce periodic safety update reports for Class IIa and above, and feed clinical follow-up data back into the clinical evaluation on a defined cycle.

The US has post-market obligations too, chiefly complaint handling, medical device reporting, and corrections and removals, but they are less prescriptive about cadence. The EU model assumes your file is a living document updated whether or not anything went wrong.

Which Market to Enter First

For most US-based companies, the US comes first. Your first customers, clinical advisors, reimbursement pathway, and investors are there, the review timeline is shorter and more predictable, and you can clear a device before your quality system is fully mature. Europe follows once revenue exists to fund a Notified Body engagement.

Go to Europe first only for specific reasons: no viable US predicate but a clean fit under an EU classification rule, European clinical partners and early adopters, or a materially stronger reimbursement case there. The historic argument for Europe first, that CE marking was faster and cheaper, has largely reversed under the current regulation.

Whichever order you pick, build one technical file designed for both. Risk management, biocompatibility, electrical safety, software documentation, and usability engineering are largely shared. Clinical evidence strategy and labeling are where they diverge, and those are worth planning in parallel rather than sequentially.

Plan Both Pathways From One File

Projects House helps device developers map classification in both jurisdictions, choose a sequence, and structure a single technical file that feeds an FDA submission and an EU technical documentation package without duplicating the testing. Send your intended use statement and device description through our contact form.