Melatonin typically takes between 20 minutes and 2 hours to start working, with many people feeling its effects around 30 minutes to an hour after taking it. The recommendation is often to take melatonin about 1 to 2 hours before bedtime to align with the body's natural melatonin increase. The exact time it takes can vary by individual and the type of melatonin supplement used (immediate-release vs extended-release).

Key Details:

• Usual onset time: 20 minutes to 2 hours.
• Common advice: Take 1-3 mg about 1-2 hours before sleep.
• Extended-release versions may take longer to peak but help maintain sleep.
• Some report feeling effects in as little as 20 to 30 minutes.
• Melatonin levels naturally begin to rise around 2 hours before typical bedtime, which supplements aim to mimic.

This means to maximize effectiveness, melatonin should be taken sufficiently ahead of the intended sleep time for the best results.