Tax & Compliance

Tax Registration & Exemption

Complete guides for EIN registration, S-Corp elections, sales tax permits, nonprofit 501(c)(3) exemptions, and payroll tax setup.

Tax Registration Overview

Every business entity needs the right federal and state tax registrations — from your EIN (Employer Identification Number) to sales tax permits, payroll withholding, and nonprofit exemptions. The guides below cover every tax registration type your LLC, Corporation, S-Corp, or Nonprofit may need.

Guides5 Topics
FederalEIN · S-Corp
StateSales · Payroll
Exemptions501(c)(3)
Entity TypesLLC · Corp · NP
Updated2026

Federal Tax Registrations

Federal tax registration requirements, including your Employer Identification Number and S-Corporation election with the IRS.

Federal — IRS Registration

Employer Identification Number (EIN)Federal Tax Identification Number
LLCCorporationNonprofitS-Corp

An EIN (also called a FEIN or Tax ID Number) is a 9-digit number assigned by the IRS to identify your business entity for federal tax purposes. Required for all business entities to open bank accounts, hire employees, and file taxes.

Requirements

  • Required for all LLCs and Corporations with employees
  • Required to open business bank accounts
  • Required for S-Corp election (Form 2553)
  • Required for Nonprofit 501(c)(3) application
  • Single-member LLCs may use SSN but EIN recommended for privacy

Steps to Register

  1. Apply online at IRS.gov (instant for US-based entities)
  2. International applicants must fax or mail Form SS-4
  3. EIN issued immediately upon successful application
  4. EntityEngine handles EIN applications as part of formation
S-Corporation Tax ElectionIRS Form 2553 — Election by a Small Business Corporation
LLCCorporation

S-Corp status allows qualifying corporations and LLCs to elect pass-through taxation, avoiding corporate double taxation while maintaining corporate structure benefits.

Requirements

  • Entity must already exist (LLC or Corporation)
  • Must have an EIN before filing Form 2553
  • All shareholders must be US citizens or residents
  • Maximum 100 shareholders allowed
  • Only one class of stock permitted
  • File by March 15 for current tax year (or within 75 days of formation)

Steps to Register

  1. Confirm all eligibility criteria are met
  2. Complete IRS Form 2553 with all shareholder signatures
  3. File by March 15 or within 75 days of entity formation
  4. IRS sends CP261 Notice confirming S-Corp election
  5. EntityEngine assists with S-Corp election as part of formation

State Tax Registrations

State-level tax registration, including sales tax permits and payroll tax withholding — required for most businesses operating in or selling to customers in each state.

State Revenue Registrations

State Sales Tax RegistrationNexus, Permits, and Rates by State
LLCCorporationSole Prop

If you sell goods or taxable services, you may be required to collect and remit sales tax in states where you have "nexus" — a sufficient business presence, either physical or economic.

Requirements

  • Physical presence (office, warehouse, employees) creates nexus
  • Economic nexus: $100,000+ in sales or 200+ transactions
  • 45 states + DC have a state sales tax
  • Alaska, Delaware, Montana, New Hampshire, Oregon — no state sales tax

Steps to Register

  1. Determine which states you have nexus in
  2. Register for a Sales Tax Permit with each state's revenue department
  3. Configure billing system to collect the correct rates
  4. File returns on the required schedule (monthly, quarterly, or annual)
Payroll Tax RegistrationFederal and State Employer Tax Requirements
LLCCorporationS-CorpNonprofit

If you hire employees, you must register for federal and state payroll tax accounts and withhold applicable taxes from employee wages, including income tax, Social Security, and Medicare.

Requirements

  • EIN required before setting up payroll
  • Federal: IRS account for 941 quarterly payroll tax returns
  • State: Register with each state where you have employees
  • Withhold federal income tax, Social Security (6.2%), and Medicare (1.45%)
  • Match employee Social Security and Medicare contributions

Steps to Register

  1. Obtain your EIN from the IRS
  2. Register with EFTPS (Electronic Federal Tax Payment System)
  3. Register for state income tax withholding in each state
  4. Register for state unemployment insurance (SUI)
  5. Set up payroll processing with your payroll provider

Tax Exemptions

Tax-exempt status for qualifying charitable, educational, and religious organizations — including IRS 501(c)(3) applications and state-level exemptions.

IRS Tax Exemption

Nonprofit 501(c)(3) Tax ExemptionIRS Tax Exemption for Charitable Organizations
Nonprofit

A 501(c)(3) designation exempts your nonprofit organization from federal income tax and allows donors to deduct their contributions. This is the most common tax-exempt status for charitable organizations.

Requirements

  • Form and register a nonprofit corporation in your state first
  • Must have charitable, educational, religious, scientific, or literary purpose
  • No private inurement — earnings cannot benefit insiders
  • Limited political activity and lobbying
  • Assets must be dedicated to exempt purposes on dissolution

Steps to Apply

  1. Form a nonprofit corporation with your state Secretary of State
  2. Draft bylaws with required 501(c)(3) language
  3. Apply using IRS Form 1023 or 1023-EZ (smaller organizations)
  4. Pay IRS filing fee ($275 for 1023-EZ or $600 for 1023)
  5. IRS issues determination letter (typically 3–12 months)
  6. Apply for state tax exemption separately in most states

Get your tax registrations handled — automatically.

AI-powered entity formation, EIN registration, and compliance tracking — everything you need to stay tax-compliant from day one.