> ## Documentation Index
> Fetch the complete documentation index at: https://docs.symmetry.com/llms.txt
> Use this file to discover all available pages before exploring further.

# What is Symmetry Payroll Forms?

> Automated federal, state, and local employee withholding forms for the U.S. and Canada: determined, completed, and returned as signed PDFs and structured tax data.

Symmetry Payroll Forms (SPF) automates the employee withholding form process for the United States and Canada. Give SPF an employee's home and work addresses, and it determines which federal, state, and local withholding forms they're required to complete, guides them through completing each one, and returns a signed PDF along with their elections as structured data.

Symmetry maintains the forms as jurisdictions revise them. New form versions take effect on their published effective dates without any change to your integration code.

## What SPF handles

<Columns cols={2}>
  <Card title="Determining the forms">
    Resolves home and work addresses to taxing jurisdictions and returns the applicable forms, accounting for reciprocal agreements, nexus, local jurisdictions, and lock-in letters.
  </Card>

  <Card title="Guiding the employee">
    Serves each form as a sequence of questions, branching on the employee's answers so they only see the questions that apply to them.
  </Card>

  <Card title="Producing the document">
    Fills and signs the official government PDF, including the [penalty of perjury declaration](/spf/core-concepts/penalty-of-perjury-statements) and jurisdiction-required instructional text.
  </Card>

  <Card title="Returning the elections">
    Hands back the employee's withholding elections as structured tax parameters your payroll system can consume directly.
  </Card>
</Columns>

SPF does all four the same way whichever implementation you choose. For the end-to-end flow (the five stages every integration moves through), see [Core concepts](/spf/core-concepts/overview).

SPF supports more than 160 withholding forms across the U.S. and Canada: federal, state, territory, local, nonresident, exemption, and military spouse forms, plus the full Canadian TD1 family and Quebec's source deductions forms. See [Form coverage](/spf/overview/coverage) for the breakdown, or the [SPF catalog](/spf/references/tax-parameter-catalog-and-schema) for the complete list.

<Note>
  **SPF does not calculate withholding.**

  SPF establishes what an employee's withholding elections *are*. Turning those elections into a dollar amount on a paycheck is the job of your payroll engine, or of the [Symmetry Tax Engine](/ste/overview/what-is-the-ste) if you license it. If you use both, the [tax parameter mapping](/spf/references/ste-tax-parameter-mapping) connects them.
</Note>

## Nothing is stored

SPF is a pass-through. It does not retain employee answers, completed forms, or personal data: names, Social Security numbers, and addresses flow from your request to your response and are not kept. Symmetry tracks only which form IDs were completed, as an aggregate usage metric.

This is deliberate. Employee PII never rests in Symmetry's systems, which keeps SPF out of your data-retention and breach-exposure surface entirely. Because you remain the system of record, store the PDF and tax parameters when SPF returns them. See [SPF data retention](/spf/references/data-retention).

## Next steps

<CardGroup cols={2}>
  <Card title="Implementation types" icon="scale-balanced" href="/spf/overview/implementation-types">
    Choose between the API, the Hosted UI, and On-Premise.
  </Card>

  <Card title="Core concepts" icon="lightbulb" href="/spf/core-concepts/overview">
    The ideas that apply to every SPF integration.
  </Card>

  <Card title="Form coverage" icon="map" href="/spf/overview/coverage">
    The jurisdictions and form types SPF supports.
  </Card>

  <Card title="Licensing" icon="key" href="/spf/overview/licensing">
    How licensing and authentication work.
  </Card>
</CardGroup>