The North Atlantic Treaty Organization
NATO is a military alliance of 32 member states bound by collective defence under Article 5 of the North Atlantic Treaty. This reference lists each member with the year it joined and its approximate defence spending as a share of GDP, measured against the alliance’s 2% guideline.
How it works
Each member carries an accession year — 1949 for the twelve founding signatories
— and an estimated defence-spending figure as a percentage of GDP. The 2%
guideline is a political target agreed by members; the filter lets you show only
those meeting it or only those below it. Spending shares are approximate and move
year to year.
Notes and example
- The alliance began with 12 founders signing the treaty in Washington in 1949.
- Finland (2023) and Sweden (2024) are the two newest members.
- The 2% of GDP guideline is a political aim, not a binding obligation.
- Article 5 — an attack on one is an attack on all — has been invoked once, after the September 2001 attacks on the United States.