Why Some Countries Weekend on Friday–Saturday Instead of Saturday–Sunday
It's easy to assume the weekend is just a fixed, natural fact — five days of work, then Saturday and Sunday off. But on our Bangladesh page and our UAE page, the calendar grid shades Friday and Saturday (or, for the UAE today, Saturday and Sunday) differently than it does on the India or US pages — because "the weekend" is a convention, not a constant, and different countries have landed on different answers for very different reasons.
Where Friday comes from
In Islam, Friday (Jumu'ah) is the day of the week's main congregational prayer, which is traditionally held around midday — making a full working Friday impractical in Muslim-majority societies. That's the root of the Friday-centred weekend used across much of the Islamic world. Historically, the most common pattern in the Gulf and wider Middle East paired Thursday and Friday as the weekend, with the working week running Saturday to Wednesday. A smaller group of countries — Djibouti, Iran and Somalia among them — kept (and some still keep) a single Friday-only rest day rather than a full two-day weekend.
The Gulf's switch away from Thursday-Friday
The Thursday-Friday weekend held for decades, but it created a real friction: it left only a one-day overlap with the Saturday-Sunday weekend used by most of the rest of the world's financial markets, which made coordinating trade, banking and travel genuinely harder. Saudi Arabia moved first, officially shifting its weekend from Thursday-Friday to Friday-Saturday effective June 29, 2013 — the Saudi Press Agency framed it as a move toward "the largest homogeneity of weekly working days" with other Gulf Cooperation Council states and international partners, citing the economic cost of the mismatch. Oman made the identical change just two months earlier, effective May 1, 2013, for the same stated reason: aligning with its Gulf neighbors. Within a few years, Friday-Saturday had become the standard weekend across almost the entire Gulf.
Bangladesh: a different weekend, a different reason entirely
Bangladesh also uses a Friday-Saturday weekend today — reflected directly in our Bangladesh calendar, where the working week runs Sunday to Thursday — but it didn't arrive there by following Gulf convention. Bangladesh's single weekly holiday had long been Friday alone; the second day off, Saturday, was added starting September 9, 2005, and the government's own stated reason wasn't religious alignment but energy policy: a sharp rise in global crude oil prices had just pushed domestic fuel costs up, and an extra non-working day was intended to meaningfully cut fuel-powered transport use across government, semi-government and autonomous offices. Civil servants worked an extra hour on the remaining weekdays to offset the lost day. It's a reminder that two countries can end up with the identical Friday-Saturday weekend on paper for almost entirely unrelated reasons — one rooted in religious practice and regional coordination, the other in a 2005 energy-price shock.
The UAE's second switch: from Friday-Saturday to Saturday-Sunday
The UAE's weekend history shows just how much this keeps evolving even after a country settles into the Gulf-standard pattern. Having used Friday-Saturday like its neighbors, the UAE changed again — this time to a Saturday-Sunday weekend with Friday as a half working day — effective January 1, 2022, a shift federal authorities explicitly tied to aligning the country's business week more closely with global markets. Sharjah went further, giving government employees Friday off entirely alongside the full weekend. Our UAE page reflects this current Saturday-Sunday pattern, since that's what applies today — a useful reminder that a country's weekend convention isn't necessarily a permanent cultural fact; it can be a policy lever a government adjusts as its trade relationships shift.
Why this matters for a calendar that covers 27 countries
A single hard-coded "weekend = Saturday and Sunday" rule would quietly be wrong for a meaningful share of the countries we cover. Under the hood, each country page on Tomorrow Calendar carries its own weekend definition — Saturday-Sunday by default, with an explicit override for the handful of countries (Bangladesh among them) that differ — so the monthly calendar grid, the "is tomorrow a weekend" check and the day-of-week shading are all correct for the country you're actually looking at, not just for whichever convention happens to be most common globally. If you're curious how day-of-week logic works more generally, see our piece on why some countries start the week on Sunday — a related but separate question, since where a week starts and which two days end it are independent conventions that don't always line up the way you'd expect.