RM Williams boot sizing can feel a little different if you’re used to US brands. That’s where the RM Williams size chart and width chart come in—they’re your roadmap to finding the right fit.
Here’s the thing: RM Williams uses Australian sizing numbers, which are different from US sizes. If you’re a US 9, that’s a UK/AU 8. Confusing? A little.
But don’t worry—the size charts below will help you convert your US size to the right AU size, so you can skip the guesswork.
First, if you really want to dive into the nitty-gritty of sizing, here’s everything you need to know about how RM Williams sizing works.
Let’s dive right into it…
RM Williams Size Chart
The size chart is your cheat sheet for converting your US size to the right RM Williams size. Without it, you’re left guessing—and trust me, guessing with boots this nice is a risky move. The chart simplifies the process, so you can skip the headache and focus on finding your perfect pair.
Men
*Australian/UK is one number down from US sizing.
| RMW/AU/UK | US Mens | EU | Length (CM) |
|---|---|---|---|
| 1 | 20.9 | ||
| 1.5 | 21.3 | ||
| 2 | 3 | 21.7 | |
| 2.5 | 3.5 | 22.1 | |
| 3 | 4 | 35 | 22.6 |
| 3.5 | 4.5 | 36 | 23 |
| 4 | 5 | 36.5 | 23.4 |
| 4.5 | 5.5 | 37 | 23.8 |
| 5 | 6 | 38 | 24.2 |
| 5.5 | 6.5 | 38.5 | 24.7 |
| 6 | 7 | 39 | 25.1 |
| 6.5 | 7.5 | 40 | 25.5 |
| 7 | 8 | 41 | 25.9 |
| 7.5 | 8.5 | 41.5 | 26.3 |
| 8 | 9 | 42 | 26.8 |
| 8.5 | 9.5 | 43 | 27.2 |
| 9 | 10 | 43.5 | 27.6 |
| 9.5 | 10.5 | 44 | 28 |
| 10 | 11 | 45 | 28.4 |
| 10.5 | 11.5 | 45.5 | 28.9 |
| 11 | 12 | 46 | 29.3 |
| 11.5 | 12.5 | 46.5 | 29.7 |
| 12 | 13 | 47 | 30.1 |
| 12.5 | 13.5 | 47.5 | 30.5 |
| 13 | 14 | 48 | 31 |
| 13.5 | 14.5 | 31.4 | |
| 14 | 15 | 31.8 | |
| 14.5 | 15.5 | 32.2 | |
| 15 | 16 | 32.6 | |
| 15.5 | 16.5 | 33.1 | |
| 16 | 17 | 33.5 | |
| 16.5 | 17.5 | 33.9 | |
| 17 | 18 | 34.3 |
Related: Blundstone Boost Size Chart
Women
| RMW | UK | US | EU | Length (CM) |
|---|---|---|---|---|
| 5 | 2.5 | 5 | 22.1 | |
| 5.5 | 3 | 5.5 | 35 | 22.6 |
| 6 | 3.5 | 6 | 36 | 23 |
| 6.5 | 4 | 6.5 | 36.5 | 23.4 |
| 7 | 4.5 | 7 | 37 | 23.8 |
| 7.5 | 5 | 7.5 | 38 | 24.2 |
| 8 | 5.5 | 8 | 38.5 | 24.7 |
| 8.5 | 6 | 8.5 | 39 | 25.1 |
| 9 | 6.5 | 9 | 40 | 25.5 |
| 9.5 | 7 | 9.5 | 41 | 25.9 |
| 10 | 7.5 | 10 | 41.5 | 26.3 |
| 10.5 | 8 | 10.5 | 42 | 26.8 |
| 11 | 8.5 | 11 | 43 | 27.2 |
Related: Wolverine Boost Size Chart
Related:
After figuring out your RM Williams size, swing by our Ecco Size Chart Guide to see how their European sizing stacks up—it’s simpler than you think!
RM Williams Men’s Width Chart
*Each width option adds about 0.64cm (1/4 inch) of extra room in the footbed compared to the previous width, all within the same size.
| RMW/AU/UK | Narrow - F (CM) | Regular - G (CM) | Wide - H (CM) | Extra wide - X (CM) |
|---|---|---|---|---|
| 1 | 19.7 | 20.3 | 21 | |
| 1.5 | 20 | 20.6 | 21.3 | |
| 2 | 20.3 | 21 | 21.6 | |
| 2.5 | 20.6 | 21.3 | 21.9 | |
| 3 | 21 | 21.6 | 22.3 | |
| 3.5 | 21.3 | 21.9 | 22.6 | |
| 4 | 21.6 | 22.3 | 22.9 | 24.1 |
| 4.5 | 21.9 | 22.6 | 23.2 | 24.4 |
| 5 | 22.3 | 22.9 | 23.5 | 24.8 |
| 5.5 | 22.6 | 23.2 | 23.8 | 25.1 |
| 6 | 22.9 | 23.5 | 24.1 | 25.4 |
| 6.5 | 23.2 | 23.8 | 24.4 | 25.7 |
| 7 | 23.5 | 24.1 | 24.8 | 26 |
| 7.5 | 23.8 | 24.4 | 25.1 | 26.3 |
| 8 | 24.1 | 24.8 | 25.4 | 26.7 |
| 8.5 | 24.4 | 25.1 | 25.7 | 27 |
| 9 | 24.8 | 25.4 | 26./td> | 27.3 |
| 9.5 | 25.1 | 25.7 | 26.3 | 27.6 |
| 10 | 25.4 | 26 | 26.7 | 28 |
| 10.5 | 25.7 | 26.3 | 27 | 28.3 |
| 11 | 26 | 26.7 | 27.3 | 28.6 |
| 11.5 | 26.3 | 27 | 27.6 | 28.9 |
| 12 | 26.7 | 27.3 | 28 | 29.3 |
| 12.5 | 27 | 27.6 | 28.3 | 29.6 |
| 13 | 27.3 | 28 | 28.6 | 29.9 |
| 13.5 | 27.6 | 28.3 | 28.9 | 30.2 |
| 14 | 28 | 28.6 | 29.3 | 30.5 |
| 14.5 | 28.3 | 28.9 | 29.6 | |
| 15 | 28.6 | 29.3 | 29.9 | |
| 15.5 | 28.9 | 29.6 | 30.2 | |
| 16 | 29.3 | 29.9 | 30.5 | |
| 16.5 | 29.6 | 30.2 | 30.9 | |
| 17 | 29.9 | 30.5 | 31.2 |
Related: Alden Size Chart
RM Williams Women’s Width Chart
*Each width option adds about 0.64cm (1/4 inch) of extra room in the footbed compared to the previous width, all within the same size.
| RMW | Regular - D (CM) | Wide -E (CM) |
|---|---|---|
| 5 | 20.6 | 21.3 |
| 5.5 | 21 | 21.6 |
| 6 | 21.3 | 21.9 |
| 6.5 | 21.6 | 22.3 |
| 7 | 21.9 | 22.6 |
| 7.5 | 22.3 | 22.9 |
| 8 | 22.6 | 23.2 |
| 8.5 | 22.9 | 23.5 |
| 9 | 23.2 | 23.8 |
| 9.5 | 23.5 | 24.1 |
| 10 | 23.8 | 24.4 |
| 10.5 | 24.1 | 24.8 |
| 11 | 24.4 | 25.1 |
Related: Thorogood Size Chart
Still unsure how to measure your feet? RM Williams has a handy sizing walkthrough on their website. Check out the GIF below to see exactly how it’s done!
How to Measure Your Feet Correctly
Let’s get one thing straight: the best way to know how a boot fits is to try it on in-store. Nothing beats slipping your foot into the actual boot, walking around, and feeling how it fits.
If you’re lucky enough to live near a store that carries RM Williams, grab that opportunity. A professional can measure your feet using a Brannock device, which gives you the most accurate length, width, and arch measurements.
But let’s be real—not everyone has access to a store. If you’re measuring at home, here’s how to do it right:
1. Using a Brannock Device at Home
If you’ve got a Brannock device (lucky you!), here’s how to use it:
- Stand on the device with your heel against the back.
- Check where your longest toe lands for the length.
- Slide the width bar to the widest part of your foot for the width.
- Measure both feet and use the larger size.
Related: Thursday Size Chart
2. Printable Brannock Chart
If you don’t have a Brannock, you can download a printable Brannock online for men and women. Just make sure it’s scaled correctly, place your foot on the chart, and mark where your heel and longest toe land. Measure the distance and compare it to the size guide.
3. The Traditional Method
If you don’t have a Brannock or a printable version, you can still measure your feet the old-fashioned way:
- Grab a piece of paper, a pencil, and a ruler.
- Stand on the paper and trace your foot.
- Measure the length from heel to toe and the width at the widest part.
- Compare your measurements to the RM Williams size chart.
Pro Tips for Measuring at Home
- Measure at the end of the day when your feet are slightly swollen.
- Wear the socks you plan to wear with the boots.
- Measure both feet—most people have one foot slightly larger than the other.
Related: Grenson Size Chart
RM Williams Sizing FAQ
Are R.M.Williams true to size?
Yes and no—it depends on the model and your foot shape. RM Williams boots are designed to fit true to size based on your Brannock measurement, but their lasts (the molds that shape the boots) are on the slim side. This means that while the length might match your true size, the fit can feel snug, especially in the width. For example, if you’re a US 8.5D, you’d typically go with a UK 7.5G in RM Williams sizing. However, if you have wider feet or prefer a bit more room, you might need to size up to an 8G or even opt for the H width.
Related: Red Wing Size Chart
What is the difference between G-fit and H-fit?
The difference between RM Williams G-Fit and H-Fit comes down to width—and it’s a small but important distinction. G-Fit is RM Williams’ standard width, equivalent to a US D width. It’s designed for average-width feet and offers a snug, tailored fit.
However, because RM Williams lasts are slim, even the G width can feel a bit narrow for some people. The H-Fit is the wide width option, equivalent to a US E width.
It provides about 0.64cm (1/4 inch) more room in the forefoot compared to the G width, making it a better choice if you have wider feet or just prefer a bit more space.
Here’s the key: if your feet are on the wider side or you often find standard widths too tight, the H-Fit is the way to go. But if you have narrow to average-width feet, the G-Fit will give you that sleek, glove-like fit RM Williams is known for.
What is RM shoe size?
RM Williams uses Australian/UK sizing, which is different from US sizing. UK/AU sizing is one number down from US sizing. For example, if you’re a US men’s 9, that’s a UK/AU 8 in RM Williams. They also use unique width fittings: F (narrow), G (regular), H (wide), and X (extra wide).
Related: Danner Size Chart
How tight should R.M. Williams boots be?
As Chelsea boots, RM Williams boots are designed to fit snugly. They should hug your feet like a glove, but not so tight that they pinch or hurt. Your heel should feel secure, with just a tiny bit of slip when they’re new (this will go away as they break in). The instep should be snug but not uncomfortable, and your toes should have enough room to wiggle with about a thumb’s width of space at the front.
Do you need to break in R.M. Williams boots?
Yes, but not in the way you might think. RM Williams boots are known for being comfortable right out of the box, thanks to their high-quality yearling leather and thoughtful design. However, they will still mold to your feet over time and become even more personalized to your shape.
Does R.M. Williams run small?
Not exactly—RM Williams boots are designed to fit true to size based on your Brannock measurement. However, their lasts are on the slim side, which can make them feel tighter than you might expect, especially in the width. So, while they don’t technically run small, the slim design means you might need to adjust your size or width depending on your foot shape.