Below is a list of leading national suppliers of round rolled aluminum bars in the United Kingdom, formatted in Markdown:

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Leading Suppliers of Round Rolled Aluminium Bars in the UK

1. Aluminium Warehouse

   • Website: aluminiumwarehouse.co.uk
   • Overview: A large stockholder of aluminium products, offering a wide range of extrusions, sheets, and bars.

2. Aluminium Alloys

   • Website: aluminiumalloys.co.uk
   • Overview: Specializes in the supply and processing of aluminium and non-ferrous alloys for various industries.

3. Balmoral Tanks

   • Website: balmoraltanks.com
   • Overview: While primarily focused on water tanks and vessels, they also supply various types of rolled aluminum products.

4. Metal Mania

   • Website: metalmaniauk.co.uk
   • Overview: A supplier of metals including rolled aluminum bars, catering to diverse industrial applications.

5. Able Aluminium

   • Website: ablealuminium.co.uk
   • Overview: Offers a comprehensive range of aluminium products, including round bars, with a focus on customer service.

6. Hollinwood Aluminium

   • Website: hollinwoodaluminium.com
   • Overview: A leading manufacturer and supplier of aluminium products, including bespoke solutions for round bars.

7. Birmingham Aluminium

   • Website: birminghamaluminium.com
   • Overview: A supplier of aluminium extrusions and rolled products, including round bars for various applications.

8. AluStock

   • Website: alustock.co.uk
   • Overview: Specializes in stockholding and distribution of aluminium products, including round bars particularly aimed at fabricators and manufacturers.

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Be sure to verify the current status and offerings of each company, as the market can change frequently. If you need more specific information or trends in the aluminum industry, please let me know!