30-Day Water Challenge with a Friend

What it is

The challenge: drink your daily water target every day for 30 days. The template uses 64 oz, about 2 litres, but the number is yours to agree on. Water, sparkling water and herbal tea count; decide with your partner about coffee and other drinks.

Drinking enough water is easy to forget rather than hard to do. A partner checking in at the end of the day is a reminder that doesn't come from a notification you've learned to swipe away.

Thirty days is enough for the refills to become automatic, which is the only part of this challenge that's actually hard.

How to do it

1. Pick a bottle and work out how many refills make your target.
2. Tie refills to fixed moments: waking up, each meal, the end of work.
3. Check in once you've hit your target for the day.
4. If you've been told to limit fluids for a medical reason, follow your doctor's advice, not the template.

Day by day

1. Days 1–3

   Set it up

   Pick the bottle, the target and the refill moments, and tell your partner. Fill the bottle before bed so it's waiting in the morning.

2. Days 4–10

   The novelty wears off

   You may be surprised how little you were drinking. Send your partner a halfway update at lunch; it's much easier to finish when you're halfway by midday.

3. Days 11–24

   The long middle

   The bottle gets left behind and busy days come up short. Keep one at work and one at home, and agree on a single evening check-in time with your partner.

4. Days 25–30

   The finish line

   Keep the refill moments that worked. Water is one of the easiest habits to keep after a challenge, as long as the bottle stays where you'll see it.

Where people quit, and how a partner helps

• The forgotten bottle

  Leaving the bottle at home is the most common reason for a short day. Keep a second one wherever you spend your day.

• The evening catch-up

  Drinking it all at 9pm is miserable and keeps you up. A midday message from your partner saying they're halfway is the nudge to keep pace.

• The cold-weather dip

  People drink less when it's cold. Herbal tea counts if you agree it does, so the habit survives the winter.

Your 30-day tracker

Print this page, or tick the boxes here. Ticks are saved in this browser only. In the app, you and your partner see each other's check-ins as they happen. One tick a day.

How to start it in the app

1. Create your free account, then install Friends with Habits from Google Play and sign in.
2. Tap New Pact and pick “Drink 64oz water” under Health & Body.
3. Keep the schedule the template suggests: every day.
4. Invite your friend by link, text or email. Once they accept, you both check in each day and see each other's progress.
5. A pact in the app runs 30 days, so this whole challenge is one pact.

Questions