# TaxPrepServiceHQ > Data-driven tax resources for US taxpayers: credentialed preparer counts, IRS filing > statistics by city/ZIP, notice-code references, calculators, and a public JSON API. > Built on IRS public datasets (PTIN FOIA extracts + SOI individual income statistics). > Not affiliated with the IRS. Not tax or legal advice. ## Coverage - 810,508 credentialed tax preparers (CPAs, EAs, attorneys) mapped to cities - IRS SOI filing statistics for 27,589 ZIP codes: returns, AGI, refunds, self-employment - 10 service verticals; 51 states + DC ## Machine-readable surface - Public JSON API: /api/v1/ (states, cities, ZIPs — CC-BY-4.0) - Markdown mirrors: append .md to any content URL (e.g. /texas/austin/index.md) - Open data hub: /data/ ## Key sections - State hubs: /{state-slug}/ (e.g. /texas/, /california/) - City guides: /{state-slug}/{city-slug}/ - Service pages: /services/{service}/ and /{state}/{city}/{service}/ - IRS notices: /notices/ · Transcript codes: /transcript-codes/ - Calculators: /calculators/ · Guides: /guides/ ## Services covered - Tax Preparation: Get your federal and state returns prepared and filed correctly. - Tax Relief & Resolution: Owe back taxes? Specialists negotiate with the IRS on your behalf. - Back Taxes & Unfiled Returns: Catch up on years of unfiled returns before the IRS files for you. - Audit Representation: A CPA, EA, or tax attorney deals with the IRS so you don't have to. - Business & S-Corp Tax: Entity returns, payroll tax, deductions, and quarterly planning. - Self-Employed & 1099 Taxes: Schedule C, quarterly estimates, and deductions for freelancers and gig workers. - Crypto & Digital Asset Taxes: Capital gains, DeFi, staking, and the 1099-DA era of crypto reporting. - Amended Returns (1040-X): Fix a filed return — missed credits, wrong status, forgotten income. - Filing Extensions: More time to file (not to pay) — Form 4868 and what it really does. - IRS Notice Help: Got a letter? Know exactly what it means and what happens next. ## Attribution Data: IRS PTIN FOIA extracts, IRS SOI ZIP statistics, Census-aligned geography (SimpleMaps, CC-BY). Reuse welcome with attribution to taxprepservicehq.com.