How long do I have to file abroad after a US patent application?

Under the Paris Convention you have 12 months from your earliest filing (e.g. a provisional) to file abroad or file a PCT application and still claim priority back to that date. Miss it and you generally lose priority.

What is the 30-month PCT deadline?

If you file via the PCT, you typically have 30 months from your earliest priority date to enter the national or regional phase in each country where you want a patent. A few jurisdictions allow 31 months.

When does a provisional patent application expire?

A US provisional lasts 12 months and cannot be extended. You must file a non-provisional (or PCT) application claiming the provisional within that year, or its benefit is lost.

Patent tool

Patent Filing Deadline Calculator

Enter your earliest filing or priority date and what you filed. We'll map the deadlines that follow — the Paris/PCT priority year, the 18-month publication, the 30-month national-phase entry, and the 20-year term.

Filing / priority dateWhat did you file?

Dates use the standard month counts (12 / 18 / 30 / 240 months) measured from the date you enter, with end-of-month clamping. A few jurisdictions allow 31-month national-phase entry, and the real term can shift with patent-term adjustment. This is general information, not legal advice — confirm every deadline with a registered practitioner.

Where this fits · The patent process

Stage 05 / 08File with the USPTO

Keep going · Related guides

How to File a PatentEvery step from idea to filingRead →Provisional vs Non-ProvisionalWhich application to file firstRead →Office Action Deadline CalculatorResponse deadlines and extension fees for an Office Action.Read →Is My Idea Patentable?Run an idea through novelty, non-obviousness, utility, and eligibility.Read →How Examination WorksThe examiner's-eye viewRead →