FTB Publication 1001: Supplemental Guidelines to California Adjustments Explained

FTB Publication 1001, issued by the California Franchise Tax Board, is a reference guide rather than a fillable tax form. It walks taxpayers through the differences between federal and California tax law that affect how income, deductions, gains, and losses are reported on a California return. Anyone who has income items that California treats differently than the IRS — think interest on certain municipal bonds, depreciation methods, or specific types of retirement income — will likely need to consult this publication when preparing Schedule CA (540) or Schedule CA (540NR).

Because California does not automatically conform to every federal tax code change, this publication exists to help residents, part-year residents, and nonresidents figure out exactly where their state return should diverge from what they already reported federally. It’s organized by topic and income category, making it easier to locate the specific adjustment that applies to a given situation rather than digging through the entire tax code.

Who Actually Needs This Publication

If you’re filing a California personal income tax return and your federal adjusted gross income includes any item California treats differently, this document applies to you. Common situations include:

• Taxpayers with out-of-state municipal bond interest that’s taxable in California but exempt federally
• People who sold a home, stock, or other asset where the basis differs between federal and state calculations
• Retirees receiving Social Security, railroad retirement, or certain pension income treated differently at the state level
• Self-employed individuals or business owners dealing with depreciation or expensing differences
• Anyone claiming HSA contributions, since California doesn’t allow the same federal HSA deduction

Tax preparers use this publication constantly since it’s essentially the roadmap for completing the adjustment columns on Schedule CA. Even taxpayers who use software still benefit from reading through the relevant sections to confirm the numbers being generated match their actual situation.

When You Need to Reference It

This publication is used during the annual filing season, typically alongside Form 540 or 540NR, whenever there’s a federal-to-state adjustment to make. It’s not something you submit with your return — instead, it’s a supporting reference that explains the mechanics behind the numbers you enter on Schedule CA. The FTB updates it yearly to reflect any new conformity or nonconformity changes between IRS rules and California statutes, so using the correct year’s version matters. Grabbing the 2025 edition rather than an older one ensures you’re working from current guidance, since tax law changes from one year to the next can shift which adjustments apply.

Businesses navigating multiple state tax credits or incentives sometimes cross-reference this publication alongside other state-specific guidance. For example, companies evaluating the California Competes Tax Credit review process often need to understand how income adjustments interact with credit eligibility. Similarly, workers or businesses dealing with multi-state tax situations — such as those reviewing New York’s semiconductor manufacturing workforce training credit or filing a Yonkers nonresident earnings tax return — know how important it is to get state-specific adjustment guidance right before submitting anything.

How to Get and Use FTB Publication 1001

This publication is not one of those interactive PDFs you can fill out on your computer. It’s meant to be printed and read, since it’s a guide rather than a form requiring entries. Once downloaded, the practical workflow looks like this:

• Identify the income or deduction item that differs between your federal and California returns
• Locate the matching section in the publication, which explains the adjustment and how to calculate it
• Apply that adjustment on the appropriate line of Schedule CA (540) or Schedule CA (540NR)
• Keep the publication or your notes on hand in case the FTB requests documentation supporting the adjustment

Since there are no fillable fields, there’s no risk of formatting errors or software glitches — you’re simply using it as a reference while completing your actual tax forms by hand or in your preparation software. Keeping a printed copy nearby during tax season, especially if your return includes several federal-state differences, saves time compared to searching the FTB website section by section every time a question comes up.