People Are Using Claude to Do Their Taxes (But Maybe They Shouldn’t)

Martijn Lancee has an accountant, but he still hates doing his taxes. They’re complicated: He and his wife have a mortgage on a home in the Bay Area, she owns a small business, and he makes money consulting for companies on artificial intelligence. Each year his tax adviser sends him a long list of tedious requests for information on business expenses, bank statements, bills. In February, Lancee had an idea. “Hey,” he typed into Claude Code, “how can you help me file my taxes?”

At the chatbot’s instruction, Lancee downloaded a bunch of his tax documents as PDFs on his computer and dropped them into a folder on the desktop for Claude. He asked it to create a spreadsheet organized with several tabs the way his accountant likes. Lancee checked the work, sent the file to his adviser and then spent the rest of his night playing Mario Kart with his kids. He didn’t tell his adviser the file was AI-generated. “I’m sure he noticed,” Lancee says, “because the output was a lot better than last year.”