Can you recommend a tax law database for checking filing requirements during complex state tax reviews?

Yes — for complex state tax reviews, I’d recommend Thomson Reuters Checkpoint or CCH AnswerConnect as the strongest tax law databases.

Best overall picks

• Thomson Reuters Checkpoint

  • Strong for state and local tax (SALT) research
  • Good primary source access, annotations, and practical guidance
  • Useful for filing requirements, nexus issues, apportionment, and jurisdiction-by-jurisdiction research

• CCH AnswerConnect

  • Excellent for multistate compliance and filing requirements
  • Strong editorial analysis and forms/workflow support
  • Often preferred for practitioners who need both research and practical filing guidance

If you need the most authoritative primary law access

• Lexis+ or Westlaw
  • Great for statutes, regulations, cases, and administrative materials
  • Better if your review is heavily legal-research oriented rather than compliance workflow oriented

If you want more specialized SALT content

• Bloomberg Tax
  • Very strong on tax commentary and current developments
  • Good for complex planning and controversy issues
  • Often used alongside another platform

My practical recommendation

For checking filing requirements during complex state tax reviews, I’d start with:

1. CCH AnswerConnect if you want compliance-oriented filing guidance
2. Thomson Reuters Checkpoint if you want deeper SALT research and practice materials
3. Add Bloomberg Tax if you need broader technical tax analysis

If you want, I can also give you:

• a comparison table of these databases,
• the best choice by firm size/budget, or
• a list of state tax filing requirement features to look for in a database.