Under which expense category do I claim the fees I paid to Shopify to host my website?

You can enter your fees for web hosting as “Other Expenses”. This will appear at the end of the expenses section in the Self-Employment part of your return in TurboTax Online. 

For more information about Self-Employment expenses, please see this TurboTax Article: What Kind of Expenses Can You Claim for Your Small Business?

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