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SiS Discount Codes

25% SiS Discount Code – Save today!

Free codes – 6 available

SiS stands for Science in Sport, and that's what you get when you shop there. SiS offers a range of sports energy gels, hydration aids, supplements, vitamins and more. Each of these products has been subject to rigorous testing and is scientifically approved. You can benefit from savings on your next order when you use your SiS discount code.

No expiry date

No expiry date

Tested on 03/01/2022

No expiry date

Valid until 31/12/2022

Tested on 03/01/2022

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30 Day Statistics: 1 new Voucher Codes added • 7 Tested by hand • Last edit on 07/01/2022

Recently Expired SiS Discount Codes & Promo Codes

Feel free to try one of these SiS discount codes that may still work.

No expiry date

No expiry date

Valid until 25/09/2021

Valid until 07/07/2021

Valid until 08/03/2021

Valid until 29/01/2021

Valid until 25/01/2021

Valid until 18/01/2021

Valid until 21/12/2020

Valid until 15/12/2020

Valid until 15/12/2020

You may also like these vouchers

Tested on 13/01/2022

Tested on 15/01/2022

Tested on 12/01/2022

Tested on 15/01/2022

Explore All Valid SiS Deals & Sales for January 2022


SiS Voucher Details



Receive 25% off all Items at SiS

No expiry date


Receive 20% off at SiS

No expiry date


Receive £20 off with this Discount Code

No expiry date


Receive £10 off with this Discount Code

No expiry date


Editor Pick: £10 off any 2 Strawberry and Lime 8 Pack Hydro with Discount Code

31 December 2022


SiS: Free SIS Premier Delivery for 1 Year

No expiry date

Useful tips and information

SiS Voucher Codes

How can I save the most money on SiS's range of products?

You'll often find impressive discounts on various products across the SiS site. However, if you want to get consistently good deals, the best way is to use your SiS voucher code. Here are some recent offers:

  • SiS discount code: Save 50% on everything.

  • SiS voucher code: Get 50% off SiS protein bars.

  • SiS promo code: Take 30% off vitamins and minerals.

How do I save with my SiS promo code?

Once you've got your SiS voucher, saving is simple. This is all you need to do:

  1. Choose your SiS discount code from our current crop of vouchers. Pick one that gives you great savings and covers your likely purchase. Then copy down the code.

  2. Browse the SiS site to find your desired items. Add them to your basket as you go and when you're done, click "View Basket" to proceed to your basket summary.

  3. On the summary page, look out for the discount code box on the right. Paste your code in here and click "Apply".

  4. You should see your savings applied to your total. Once that's confirmed, click "Proceed to Checkout" to continue to payment and delivery details.

My SiS promo code didn't have any effect. Am I doing something wrong?

We're careful to ensure that our voucher codes work reliably. If you do run into trouble, however, these steps should help you resolve it:

  • First, check that you've entered your code correctly. It's too easy to make mistakes if you type it in by hand, so we suggest you use your computer's copy and paste functions.

  • Make sure that your SiS discount code is within date. If it's expired, it won't work anymore.

  • Check the applicable categories or items for your SiS code. Some offers are restricted to certain ranges. You can find out more by reading the terms and conditions.

  • Check to see if there's a minimum spend or number of items required.

Is there a SiS sale page?

Yes, there is. SiS sale items can be found in the "Clearance" section, which you can find under the "All Products" tab in the main menu. You'll see savings of up to 70% across all ranges.

Does SiS offer a student discount?

Yes. SiS doesn't make it obvious on the home page, but you can get a SiS student discount worth 40% if you've registered with UNiDAYS.

Does SiS do free delivery?

Yes. You can get SiS free delivery when you spend at least £40. If you don't meet that spend, you'll have to pay £3.99 for standard delivery.

Does SiS have cashback?

No. There is no SiS cashback scheme.

Can I save with my first SiS order?

Yes. SiS offer promo codes for first orders when you register for the newsletter. You'll get 10% off.

Can I get special offers from SiS on social media?

Yes. Follow SiS on Facebook, Twitter, Instagram and YouTube for news, guides, advice and exclusive offers.