Hi mburwell,
Assume that you have a Single Member LLC, a disregarded entity for Federal income tax purpose. You live and work in the US. And you report your consulting business in Schedule C, Profit or Loss From Business.
https://www.irs.gov/pub/irs-pdf/f1040sc.pdf
https://www.irs.gov/pub/irs-pdf/i1040sc.pdf
The revenue from your UK international client is to be included on Part I Income line 1 Gross receipts or sales because we need to report worldwide income.
If you received in UK Pounds, you can translate into US$.
https://www.irs.gov/individuals/international-taxpayers/yearly-average-currency-exchange-rates
If foreign bank account, you might be subject to Form 8938 and FBAR requirements.
https://www.irs.gov/businesses/comparison-of-form-8938-and-fbar-requirements
Hope this helps. Thank you.
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