How Much Caffeine Is In Tims Coffee? | A Complete Breakdown

A small (12 oz) Tim Hortons regular coffee contains about 140 mg of caffeine, while a large (20 oz) contains roughly 270 mg.

You grab a Tim Hortons coffee on the way to work, and by mid-morning you’re wondering if that second cup is what’s making your heart race or if it’s just a busy day—caffeine effects typically peak within 30–60 minutes, not hours later. The caffeine content isn’t listed on the cup, and the chain doesn’t publish a standard nutrition table for its brewed coffee.

That leaves most people guessing. The honest answer is that a Tim Hortons coffee’s caffeine content varies by size, roast, and even the batch you’re drinking. Here is what the available data shows, how it compares to other chains, and how to keep your intake within recommended limits.

Caffeine By Size: Regular Brewed Coffee

The most commonly cited figures for Tim Hortons regular brewed coffee come from caffeine databases and food blogs. A small (12 oz) is reported to contain roughly 140 mg of caffeine. A medium (14 oz) bumps that to about 205 mg.

A large (20 oz) is the most popular size, and estimates typically land around 270 mg. The X-Large (24 oz) pushes closer to 330 mg. That last figure is more than three-quarters of the 400 mg daily maximum Health Canada recommends for healthy adults.

Why The Numbers Aren’t Exact

Tim Hortons doesn’t publish official caffeine data for its drip coffee, so all these numbers come from third-party testing or industry estimates. Different sources report slightly different values for the same size — one medical practice’s chart lists a large (20 oz) at 200 mg, while a dietitian’s page puts it at 240 mg.

Actual caffeine content can shift based on brew time, water temperature, and the specific coffee bean blend. A busy morning batch might extract slightly more caffeine than a slower afternoon pot.

Why The Numbers Matter More Than You Think

Caffeine affects people differently, but most adults don’t realize how quickly they can reach the upper limits. A medium Tim Hortons coffee alone contains about half the recommended daily maximum of 400 mg.

If you also have a soda in the afternoon (roughly 35-50 mg) or a pre-workout supplement (150-205 mg is common), you can easily cross 400 mg before dinner. That’s when side effects like jitters, trouble sleeping, or a racing heartbeat start appearing.

The key is knowing roughly what you’re consuming so you can track the rest of your day. A large coffee plus any other caffeinated beverage can push you past the safe zone.

• Small impact: A small (12 oz) regular coffee has about 140 mg — roughly one-third of the daily limit. Easy to pair with other drinks.
• Medium concern: A medium (14 oz) regular coffee contains around 205 mg. That’s half the daily cap in one cup.
• Large caution: A large (20 oz) regular coffee contains about 270 mg. Two of these would exceed the recommended daily limit.
• X-Large awareness: An X-Large (24 oz) regular coffee contains about 330 mg. One cup and you have just 70 mg of room for the rest of the day.

Tracking your total daily intake — not just what you drink in the morning — is the practical takeaway. Most people who feel over-caffeinated didn’t realize their “one coffee” was already most of their daily allowance.

How Tim Hortons Compares To Other Coffee Chains

Tim Hortons coffee has a caffeine concentration of roughly 0.36 mg per ml, according to caffeineinformer.com’s estimates. Starbucks drip coffee, by contrast, has about 0.70 mg per ml — almost twice as much per ounce.

That means a small (12 oz) Starbucks coffee likely contains closer to 240 mg of caffeine, while a small Tim Hortons coffee has about 140 mg. If you’re sensitive to caffeine or trying to stay under a specific limit, the chain you choose matters.

McDonald’s and Dunkin’ land in a similar range to Tim Hortons, though individual stores can vary. The real outlier is Starbucks, where a single large coffee can exceed the entire safe caffeine dose for a healthy adult in one sitting.

Dark Roast, Decaf, And Other Varieties

Tim Hortons offers dark roast and decaf options alongside its regular brew. A small (12 oz) dark roast is reported to contain about 120 mg of caffeine — slightly less than the regular blend. A medium dark roast runs about 175 mg, and a large dark roast lands around 230 mg.

Decaf has significantly less, as you’d expect. A small (12 oz) decaf has approximately 5 mg of caffeine, and a large (20 oz) has roughly 10 mg. That is negligible for most people, though those with extreme caffeine sensitivity or certain medical conditions may still want to track it.

The roast level doesn’t change caffeine content as dramatically as many people assume. The difference between regular and dark roast at Tim Hortons is modest — roughly 15-20% less caffeine in the dark roast, not a massive drop.

How To Choose Based On Your Goals

1. If you want a moderate caffeine boost: A small regular (140 mg) or small dark roast (120 mg) gives you a lift without eating up most of your daily budget.
2. If you’re limiting caffeine for health reasons: Stick to a small decaf (5 mg) or a small dark roast. Avoid the large regular (270 mg) unless it’s your only caffeine source all day.
3. If you’re comparing chains: A large Tim Hortons regular (270 mg) is roughly equivalent to a large Dunkin’ regular. A Starbucks large is significantly stronger.

Coffee chains don’t test every batch, so treat these numbers as useful estimates rather than precise values. If you consistently feel jittery or have trouble sleeping, try dropping down a size or switching to half-caff options if available.

Comparing Tim Hortons To Published Caffeine Data

The 2024 peer-reviewed study on caffeine content in popular coffees provides a helpful benchmark. It recommends a safe single dose of 200 mg and a safe daily total of 400 mg for healthy adults. A medium Tim Hortons coffee (205 mg) already exceeds that single-dose recommendation.

That doesn’t mean a medium coffee is dangerous — it means you should be mindful about consuming additional caffeine later in the day. The study’s purpose was to highlight how easily people can exceed safe limits without realizing it.

Using the small coffee caffeine figure as a starting point, a small (140 mg) is well under the 200 mg single-dose threshold. A large (270 mg) clearly exceeds it. Knowing these numbers can help you decide what size to order based on your sensitivity and schedule.

The practical takeaway: a small Tim Hortons coffee fits comfortably within safe single-dose limits, while a large or X-Large should probably be your only caffeinated drink that day.

The Bottom Line

A small Tim Hortons regular coffee has about 140 mg of caffeine, a medium around 205 mg, and a large about 270 mg. Dark roast has slightly less, and decaf is negligible. If you’re tracking total daily intake, a large coffee alone covers more than two-thirds of the 400 mg limit for healthy adults.

If caffeine affects your sleep or makes you feel jittery at specific dose levels, your doctor or a registered dietitian can help you match the right cup size to your personal tolerance rather than guessing at the drive-thru.