Daylight Saving Time and Your Birth Control Pill

You should take your birth control pill at about the same time every day to make sure you're protected against pregnancy.

Whether you take progestin-only or combination pills, taking your birth control on time gives your body the right balance of hormones to keep you from ovulating or other mechanisms to protect you from getting pregnant.

If you forget a pill or take it earlier or later than usual, it could become less effective. When daylight saving time comes around, you may wonder if it will affect the timing of your birth control.

This article will go over whether daylight saving time could change when you will need to take your birth control pill.

Packages of birth control pills with calendar background
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What Is Daylight Saving Time?

Since World War I, daylight saving time has been used in the United States and in many European countries.

During daylight saving time, you move your clocks forward during the spring/summer months by one hour. This allows daylight to last an hour longer when people are usually awake.

Places that follow daylight saving time move their clocks forward one hour near the start of spring, then turn them back to standard time in autumn. The terms "spring forward" and "fall back" are used to talk about these changes.

When It Starts and Stops

Most of the U.S. starts daylight saving time at 2 a.m. on the second Sunday in March and goes back to standard time on the first Sunday in November.

In the spring, the clocks "spring forward" from 1:59 a.m. to 3 a.m. In the fall, the clocks "fall back" from 1:59 a.m. to 1 a.m. Each time zone in the U.S. switches at a different time.

Daylight saving time was not formally adopted in the U.S. until 1918. On March 19, 1918, an official bill was created to preserve daylight and provide standard time for the U.S.

After World War I, the bill was not very popular. President Wilson ended the bill but allowed each state to decide whether to keep observing daylight saving time. States could also decide when it started and ended, which created a lot of confusion.

To make one pattern across the country, President Lyndon Johnson signed the Uniform Time Act of 1966. It was passed into law on April 13, 1966.

The act established a uniform period to observe daylight saving time. However, states could be exempt from the observation by passing a state law.

Does Everyone Change the Clocks?

Depending on where you live, you might not change the clocks twice a year. The following states and U.S. territories do not observe daylight saving time:

  • Arizona
  • Hawaii
  • American Samoa
  • Guam
  • Puerto Rico
  • The Virgin Islands
  • The Commonwealth of Northern Mariana Islands

Taking Your Pill When You "Spring Forward"

For daylight saving time, you'll move your clock ahead an hour in the spring. What will that mean for timing your birth control?

You have a two-to-three-hour window for taking your birth control pill without risking it being less effective. If you take it an hour earlier or an hour later than usual, it should still provide protection.

Let's say that you usually take your pill at 10 p.m. When daylight saving time starts, the clock moves ahead one hour overnight. You can still take your pill when the clock says 10 p.m., even though it has not been 24 full hours since your last dose.

You don't need to change the time you take your pill to match the new time. However, if it would make you feel better to adjust your timing to line up with daylight saving, you could take your pill when the clock says 11 p.m.

If you'd rather keep the time that you take your pill the same as it has been, you can make the change after the next week of placebo pills. When you start a new pack, you can go back to taking your pill at 10 p.m.

Taking Your Pill When You "Fall Back"

When daylight saving time is over in the fall, the clock is moved back one hour— or"falling back." As you did with the spring, you might want to change the timing of your pill again in the fall.

The easiest way to adjust might be to just take your pill one hour earlier than you usually do. This helps ensure you keep yourself on a good schedule and helps ensure your hormone level doesn't drop too much, which is particularly important with some progesterone-only pills

If you use an email, text, phone alarm, or birth control app to remind you to take your pill, make sure your devices have adjusted for daylight saving time.

After the week of placebo pills, you can go back to taking your pill at your usual time if you want. Just go back to your regular time when you start a new pack.

Taking your pill an hour earlier or later generally won't be a problem. However, taking your pill one hour earlier may be a slightly better option than taking it one hour later.


Birth control pills are most effective when taken at about the same time every day. During daylight saving time, your clock changes an hour. When this happens, you're essentially taking your pill earlier or later.

Experts recommend that you should take your pill within a two-to-three-hour window every day. The pill should still work fine if you take it an hour earlier or later than usual.

You can also take your pill an hour later when you "spring forward" or take it an hour earlier when you "fall back."

Whichever time you decide, you can go back to your usual time after your placebo week when you start a new pack.

A Word From Verywell

Don't worry too much about adjusting when you take your birth control pill for daylight saving time. As long as you're still taking your pill within an hour of when you normally do.

You will still have protection against pregnancy as long as you take the pill at about the same time every day.

Frequently Asked Questions

  • Why do I have to take my pill at the same time every day?

    The hormones in birth control pills stop you from ovulating or they may use other mechanisms to protect you from pregnancy.

    Your body metabolizes the hormones in the pill each day. If the level of hormones drops and a new dose isn't provided (via the next pill), you may begin ovulating again. This is especially true for progestin-only pills. If you take those pills more than 24 hours apart, you may lower the effectiveness of the pill.

  • Will changing time zones change when I have to take my pill?

    To keep yourself on the best schedule and to make sure it is effective, it is best to take your pill at the same time every day. If it's regularly taken at 10:00 a.m. Eastern time, it would need to be taken at 7:00 a.m. Pacific time.

  • What happens if I take my pill a few hours later than normal?

    The level of hormones in the body drops if a birth control pill is taken too late.

    To prevent pregnancy, it would be necessary to take the missed dose as soon as possible and then take the next pill at the regularly scheduled time (which may mean taking two pills within 24 hours). For certain progesterone-only pills, you will need a backup contraception if you take it more than three hours late.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Contraception, birth control methods.

  2. Prerau, D. Seize the daylight: the curious and contentious story of daylight saving time. New York, New York: Basic Books.

  3. Beagan, G, Wegman C. Daylight saving time 2019 ends Sunday: It's not plural and was never about the farmers. USA Today.

  4. Planned Parenthood. Can daylight savings time mess up the effectiveness of my birth control pills?.

  5. Gebel Berg E. The Chemistry of the Pill. ACS Cent Sci. 2015;1(1):5–7. doi:10.1021/acscentsci.5b00066

  6. Zwar N. Travelling with medicines. Aust Prescr. 2018;41(4):102-104. doi:10.18773%2Faustprescr.2018.034

  7. Center for Disease Control and Prevention. Recommended Actions After Late or Missed Combined Oral Contraceptives.

Additional Reading

By Dawn Stacey, PhD, LMHC
Dawn Stacey, PhD, LMHC, is a published author, college professor, and mental health consultant with over 15 years of counseling experience.