The best time to take a pregnancy test is about a week after your missed period. This timing allows for the hormone hCG (human chorionic gonadotropin), which is produced during pregnancy, to reach detectable levels in your urine. If you test too early, before hCG levels have risen sufficiently, you might get a false negative result. Some pregnancy tests claim to be accurate even before a missed period, but for the most reliable result, it's recommended to wait until at least the first day of your missed period or a week after.