Washington payroll tax and registration guide

Why is this important?

To maintain compliance with state payroll tax regulations, you must provide the following information before you can use OnPay to run payroll:

• State Employer Identification Number and state/local tax IDs
• Tax rates - State tax offices set these rates based on the type, age, and size of your business
• TPA and power of attorney - Most tax offices require this before we can submit quarterly wage reports and deposits on your behalf

This information must be provided and maintained by you in order for OnPay to accurately file and deposit tax payments for your company. OnPay is not responsible for any penalties or interest that incur due to missing or incorrect company tax information.

Each state has its own requirements, so if you pay employees in more than one state, you’ll find separate tax guides for each state.

See what information you need to provide OnPay, and what taxes and filings OnPay handles for Washington Employers.

• Information OnPay needs from you

  Use this checklist to make sure you’ve covered everything required to set up your account as a Washington employer, so OnPay can accurately file and pay taxes on your behalf:
  
  

  All Washington employers	What is this?
  Make sure your business is registered with the Washington Department of Revenue	Allows your business to file and pay taxes in Washington More info >
  Make sure your business is registered with the Washington Department of Employment Security	Allows your business to pay required unemployment insurance in Washington More info >
  Provide OnPay with your Washington ES Reference Number	The employer identification number issued by the Washington Department of Employment Security More info >
  Provide OnPay with your Washington UBI Number	A 9-digit number unique to your account with the Washington Department of Employment Security More info >
  Provide OnPay with your Washington L & I Account ID	An 8-digit number issued by the WA State Department of Labor & Industries More info >
  Provide OnPay with your Washington Unemployment (SUI) Rate	A tax rate you receive annually from the Washington Department of Labor More info >
  Provide OnPay with Standard Occupational Classification (SOC) Codes for each employee	A federal statistical standard used to classify workers into occupational categories for the purpose of collecting, calculating or disseminating data More info >
  Provide OnPay with your Washington Administrative Funding Tax Rate	A required fee that supports the administration of Washington’s UI Program More info >

• Taxes and filings OnPay handles for Washington Employers

  Unemployment Insurance Tax

  Form EMS 5208 A (Filing)	Tax Summary Form	- Quarterly
  Form EMS 5208 B (Filing)	Wage Detail	- Quarterly

  Paid Family Leave

  Paid Family Leave Report

  Washington Paid Family and Medical Leave Quarterly Return and Payment

  - Quarterly

  Washington Long-Term Cares Employee Tax

  Reported with Paid Family Leave

  Washington Paid Family and Medical Leave Quarterly Return and Payment

  - Quarterly

  Washington State Department of Labor & Industries

  L&I Quarterly Report

  Washington Workers' Compensation Quarterly Premium Report and Payment

  - Quarterly

  Other

  New Hire Report

  Washington Report of New Hires

  - As required

Where you can find the tax account numbers you need

If you are an existing employer who has previously run payroll in the state of Washington, you likely already have the IDs and online accounts needed for OnPay to process your tax filings.

If you are a new employer in Washington, you will need to register your business with the Department of Revenue and Washington Department of Labor & Industries (L&I). This must be completed for OnPay to be able to file and pay your Washington taxes.

Unified Business Identifier (UBI)

Existing Washington Employer: 

• You can find your UBI and Employment Security Account Number on the Quarterly Tax and Wage Detail Reports (Form EMS 5208 A)
• If you cannot locate this document or account number, call the Washington Department of Employment Security at (855) 829-9243 to request it

New Washington Employer: Register with the Washington Department of Revenue

• Register for a business license with the Washington Department of Revenue
  1. Click Log in
  2. Look for a “New user? Sign up” link beneath the login fields
  3. Allow up to 2 days for approval
• Once completed you will be notified of your tax deposit schedule

New Washington Employer: Register with the Washington Department of Employment Security

• When you file for a business license application with the state of Washington, the Department of Employment Security will process your application and notify the WA Department of Labor & Industries to open a workers' compensation account and the ESD to open an unemployment insurance account
• You'll receive a letter from your new Workers' Compensation account manager, and a packet of information which includes the following tax information:
  • Your Unified Business Identification (UBI)
  • Your ESD (Employment Security) Account Number (formerly known as ES Reference #)
  • Your Workers' Comp ( L&I ) Account ID
  • Your Participant Activation Code (PAC)
  • Your State Unemployment and Employment Administration Fund rate
• This letter will be sent to you 10 days after registering online (21 days if registering by mail)
• Upon receiving this letter, submit a request* to provide us with the information detailed above
• The new employer rate is a minimum of 1.00%, but is assigned based on average rates within an industry
• The wage base is $72,800

*You'll need to enter your OnPay login credentials to securely submit this information

ES (Employment Security) Account Number and Tax Rate

Updated January 1, 2025

Existing Washington Employer:

• You can find your ES Account Number on the annual Tax Rate Determination Notice received from the Washington Employment Security Department (Show me→)
• It can also be found on your Quarterly Contribution and Wage Report
• Your Unemployment Tax Rate can also be found on the annual Tax Rate Notice in box 2
• Employers in the lowest rate class pay 0.27%
• Taxable employers in the highest rate class pay 6.00% (not including delinquency or Employment Administration Fund taxes)
• The wage base is $72,800. The experience “year” WA uses to calculate tax rates is July 1 - June 30

New Washington Employer: Register with the Washington Department of Employment Security

• When you file for a business license application with the state of Washington, the Department of Employment Security will process your application and notify the WA Department of Labor & Industries to open a workers' compensation account and the ESD to open an unemployment insurance account
• You'll receive a letter from your new Workers' Compensation account manager, and a packet of information which includes the following tax information:
  • Your Unified Business Identification (UBI)
  • Your ESD (Employment Security) Account Number (formerly known as ES Reference #)
  • Your Workers' Comp ( L&I ) Account ID
  • Your Participant Activation Code (PAC)
  • Your State Unemployment and Employment Administration Fund rate
• This letter will be sent to you 10 days after registering online (21 days if registering by mail)
• Upon receiving this letter, submit a request* to provide us with the information detailed above
• The new employer rate is a minimum of 1.00%, but is assigned based on average rates within an industry
• The wage base is $72,800

*You'll need to enter your OnPay login credentials

Employment Administrative Fund Tax Rate

All Washington Employers: 

• Employment Administrative Fund tax rates are assigned by the Employment Security Department, and can be found on your annual Tax Rate Determination Notice (Show me→)
• If you are unsure of your rate, please call the agency at (360) 902-9670

Labor & Industries Tax Rates

All Washington Employers: Update Workers' Compensation Rate Code for each employee

• Workers' Comp rates will vary, depending on the job each employee performs
• The Department of L&I will assign an employer contribution rate for each job type, so it's important that you keep those rates up-to-date in OnPay
• The premium rates can change on an annual frequency
• In the event an employee changes jobs within a business, their rate will need to be updated as soon as possible, to allow OnPay to properly report their wages
• The Department of L&I gives you the option to withhold a portion of the tax from the employees
• You can update these rates in the employee profiles (Show me→)
• Rates entered incorrectly will accumulate and be paid with the rate it most closely coincides with
• Information OnPay needs to file L&I:
  • Employee premium rates
  • L&I account ID
  • UBI number

SOC (Standard Occupation Classification) Code

The state of Washington requires employers to report an SOC Code for every employee reported on the unemployment return, or the filing will be rejected by the state. For OnPay to handle this reporting for you, you must enter an SOC code to the profiles of all employees in Washington.

• To add codes to employee profiles:

  1. Go to the withholding tab of each employee's profile
  2. Look for Washington withholding details
  3. Click Select... under "SOC Code"
  4. Select the closest applicable code for the employee
  5. This change is saved automatically

  

  Repeat these steps for each employee, until you've entered an SOC code for every employee in Washington.

Paying employees in other states?

If you operate in multiple states or just have employees working from home across a state line, it's important to file the correct state forms for those workers. See what forms we file in the states where you pay employees.

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