25-Year Rule

The 25-year rule is an international debris mitigation guideline established by the Inter-Agency Space Debris Coordination Committee (IADC) and endorsed by the UN. It requires that satellites and upper stages in low Earth orbit be deorbited (or moved to a safe disposal orbit) within 25 years of end of mission. In September 2022, the US FCC adopted a stricter 5-year rule for all US-licensed LEO satellites, effective September 2024. The 25-year limit was originally chosen because natural atmospheric drag deorbits objects below 600 km within that timeframe.