Basis Says Its AI Now Finishes Tax Workbooks Twice as Fast

Basis put a brand-new AI model, GPT-6 Astra, to work on a genuinely unpleasant task: a tax workbook with 50 tabs. Think of it as one giant spreadsheet divided into 50 pages, each holding a different slice of a tax return — income here, deductions there, credits somewhere else. Astra finished that job in half the time it took GPT-5.6 Sol, the previous version of the same kind of AI, to do the same thing.

Speed alone is nice for accountants, who often bill by the hour and work brutal hours during tax season. But Basis pointed to something more interesting: Astra seemed to understand what the person actually wanted, without being told every step. Older AI tools tend to need instructions spelled out like a recipe. When a model can guess your intent, you spend less time correcting it — and you trust it more with work that matters.

The catch is that this is Basis testing a model on its own product, and announcing the result itself. There's no independent study here, and one fast result on one workbook doesn't prove the AI gets every tax question right. Tax mistakes carry real consequences, so a human preparer almost certainly still needs to review the output. Treat "twice as fast" as a promising internal number, not a guarantee.

If results like this hold up, the practical effect is straightforward: tax prep gets quicker and cheaper to produce, firms can take on more clients in the same season, and the tedious copy-and-paste drudgery that junior accountants dread shrinks. Whether any of those savings reach your bill is a separate question — companies don't always pass them along.