Zero Waste Week moves every September, so the dates you used last year won't match this time.
The rule is simple. The campaign runs the week that begins on the first Monday in September.
For 2026 that lands on Monday September 7 to Sunday September 13. Count only working days and the core challenge runs Monday September 7 to Friday September 11. Most people start on the Monday and carry the habits through the weekend.
The short answer
Zero Waste Week 2026 runs from Monday September 7 to Sunday September 13. The campaign always takes place the week beginning the first Monday in September, which is why the dates shift each year. In 2026 the first Monday lands on September 7, putting the week in ISO week 37. It's an annual awareness campaign, started in the UK in 2008 by Rachelle Strauss, that asks people, schools and workplaces to cut the waste they send to landfill or incineration for seven days.
Zero Waste Week 2026 dates
The full week runs Monday to Sunday. The active part is usually treated as a Monday to Friday effort, with the weekend used to finish projects or shop differently.
Here's how the dates fall across recent and upcoming years:
| Year | Full week (Mon to Sun) | Core days (Mon to Fri) | ISO week |
|---|---|---|---|
| 2024 | Sep 2 to Sep 8 | Sep 2 to Sep 6 | Week 36 |
| 2025 | Sep 1 to Sep 7 | Sep 1 to Sep 5 | Week 36 |
| 2026 | Sep 7 to Sep 13 | Sep 7 to Sep 11 | Week 37 |
| 2027 | Sep 6 to Sep 12 | Sep 6 to Sep 10 | Week 36 |
| 2028 | Sep 4 to Sep 10 | Sep 4 to Sep 8 | Week 36 |
Notice that 2026 is the odd one out. Most years the first Monday gives ISO week 36, but in 2026 it shifts to week 37. You can check any of these in the week calculator or see the whole year laid out on the 2026 week numbers page.
Why do the dates change every year?
Because the campaign anchors to a weekday rather than a fixed date. The first Monday in September can fall anywhere from September 1 to September 7, depending on what day the month opens on.
In 2026, September 1 is a Tuesday. So the first Monday is six days later, on September 7. You can confirm the opening weekday of any month with the weekday calculator.
There's a second layer worth knowing if you track work by week number. ISO 8601, the international standard for week numbering, starts every week on a Monday and gives week 1 to the week holding the year's first Thursday. Run Zero Waste Week through that system and 2026 sits in week 37. For the full rules, see the ISO week number guide.
If you want a one-line way to find the start date in code, this returns the first Monday of September for any year:
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What is Zero Waste Week?
Zero Waste Week is a grassroots environmental campaign that runs mainly online each September. The UK environmentalist Rachelle Strauss started it in 2008 after thinking hard about where her household rubbish actually ended up.
The idea behind it comes from a line the campaign likes: there's no such place as "away." When you throw something out, it doesn't vanish. It goes to a landfill, an incinerator or the ocean, and it usually causes harm wherever it lands.
So the week asks you to do one thing well: reduce what you bin for seven days. That can mean refusing single-use plastic, composting food scraps, repairing instead of replacing, or fitting a whole week's leftover waste into a single jar.
It's grown well beyond the UK. The campaign reports people taking part across more than 70 countries, from individual households to councils, schools and businesses who each pick their own goals.
How to take part in Zero Waste Week 2026
You don't sign up or pay anything. You pick a goal for the week of September 7 and start on the Monday.
A simple way to frame it is the waste hierarchy, often called the 5 Rs:
- Refuse what you don't need (flyers, freebies, extra packaging).
- Reduce what you do buy, choosing loose or refillable where you can.
- Reuse containers, bags and bottles instead of binning them.
- Recycle properly, checking your local council's rules so it actually gets processed.
- Rot food scraps and garden waste through composting.
Pick one R to focus on if five feels like a lot. A first-timer might just go plastic-free for the week. Someone further along might aim for a single jar of landfill waste by Sunday.
Measuring helps. Weigh your bin on Monday and again on Sunday, and the difference makes the effort real.
Households often get kids involved with a simple chart. Schools build a lesson or an assembly around it. Workplaces run a swap shop or audit the office bins. The aim is to notice how much you throw out, then change one habit that sticks past September 13.
Zero Waste Week and International Day of Zero Waste
These two get mixed up, and they're separate events.
Zero Waste Week is the week-long September campaign covered here. The International Day of Zero Waste is a single United Nations day, held every March 30 and facilitated by UNEP and UN-Habitat.
| Zero Waste Week | International Day of Zero Waste | |
|---|---|---|
| When | First full week of September (Sep 7 to 13 in 2026) | March 30 every year |
| Length | One week | One day |
| Started | 2008, by Rachelle Strauss (UK) | 2022, by the United Nations |
| Run by | Grassroots, mostly online | UNEP and UN-Habitat |
If a date you've seen says March, you're looking at the UN day. The September dates on this page are the original Zero Waste Week.
FAQ
When is Zero Waste Week 2026?
Zero Waste Week 2026 runs from Monday September 7 to Sunday September 13. The main challenge days are Monday September 7 to Friday September 11.
Why isn't Zero Waste Week on the same dates every year?
The campaign is tied to a weekday rather than a fixed date. It always starts on the first Monday in September, which can fall anywhere between September 1 and September 7 depending on the year.
What week number is Zero Waste Week 2026?
In the ISO 8601 system, Zero Waste Week 2026 falls in week 37, covering Monday September 7 to Sunday September 13. In most other years the first full September week is week 36.
Is Zero Waste Week the same as the International Day of Zero Waste?
No. Zero Waste Week is a week-long campaign in early September, started in the UK in 2008. The International Day of Zero Waste is a separate United Nations observance held on March 30 each year.
Do I have to register for Zero Waste Week?
No. It's a free, open campaign, so you just choose a waste-cutting goal and take part during the week. Plenty of people share progress online, but nothing requires you to sign up.
When is Zero Waste Week 2027?
Zero Waste Week 2027 runs from Monday September 6 to Sunday September 12, which is ISO week 36. The first Monday of September 2027 falls on the 6th.
Quick reference
- Zero Waste Week 2026: Monday September 7 to Sunday September 13 (ISO week 37).
- Core challenge days: Monday September 7 to Friday September 11.
- The rule: the week beginning the first Monday in September.
- Check any date with the week calculator and weekday calculator.
- More awareness weeks and event dates: When is.
Sources and further reading