In terms of defence expenditure as a share of GDP, the top four spenders in NATO are the United States, Greece, Estonia and the United Kingdom.

Estonia and the United Kingdom both spend 2.13% of their GDP on defence while Greece spends 2.24% and the US spends 3.42%.

The United Kingdom remains second in overall defence spending within the Alliance.

NATO collects defence expenditure data from member states on a regular basis and presents this information.

“In the figures and tables that follow, NATO also uses up-to-date economic and demographic information available from the Directorate-General for Economic and Financial Affairs of the European Commission (DG-ECFIN), and the Organisation for Economic Co-operation and Development (OECD).

In view of differences between both these sources and national GDP forecasts, and also the definition of NATO defence expenditure and national definitions, the figures shown in this report may diverge considerably from those which are quoted by media, published by national authorities or given in national budgets.

Equipment expenditure includes expenditure on major equipment as well as on research and development devoted to major equipment. Personnel expenditure includes pensions paid to retirees.”

Here’s the list of countries by defence expenditure as a share of GDP.

Here are the top five countries by total expenditure.

1. United States (730.15 billion dollars) United Kingdom (60.38 billion dollars) Germany (54.11 billion dollars) France (50.66 billion dollars) Italy (24.48 billion dollars)

The Alliance stipulate that the amounts represent payments by a national government actually made, or to be made, during the course of the fiscal year to meet the needs of its armed forces, those of their allies or of the Alliance itself.

Download the document containing the figures in PDF.