The Arizona UC-018 form is the quarterly Unemployment Tax and Wage Report that every employer covered by Arizona’s unemployment insurance program files with the Department of Economic Security (DES). It does two jobs on one form: it lists the wages you paid each employee during the quarter, and it calculates the unemployment insurance tax you owe on those wages. You file it four times a year, even for quarters when you paid no wages, either through the online Tax and Wage System or by mail.1Arizona Department of Economic Security. A Guide to Unemployment Insurance Tax and Benefits
Who Has to File
Any employer that DES has determined liable for Arizona unemployment insurance taxes files the UC-018 each quarter. When DES establishes your liability, it mails you a Determination of Unemployment Insurance Liability along with an eight-digit employer account number, which appears on every UC-018 you file from that point on.2Arizona Department of Economic Security. Applying for an Unemployment Insurance Tax Account Number
New employers pay a tax rate of 2.0 percent for at least the first two calendar years. After that, DES assigns you an experience-based rate that reflects your account balance relative to your taxable payroll.3Arizona Department of Economic Security. Employment Taxes – Calculating Unemployment Taxes DES sends you a rate notice each year, and you can also download it through the Tax and Wage System.4Arizona Department of Economic Security. Unemployment – Employer
What to Have Before You Start
Pull these items together before you sit down with the form:
- Your eight-digit employer account number, which appears on every preprinted report DES mails you.
- Total gross wages paid to each employee during the quarter. Wages include salaries, commissions, bonuses, tips, and the cash value of other compensation such as gifts.5Arizona Department of Economic Security. UC-018 – Unemployment Tax and Wage Report
- Each employee’s Social Security number and name, matching federal records.
- A count of full-time and part-time employees who worked during the payroll period that includes the 12th of each month in the quarter.6Arizona Department of Economic Security. Reporting Wages – Completing the Reports
- Your assigned tax rate for the year.
One rule shapes everything you enter: report wages in the quarter they were actually paid, not the quarter the work was performed. If an employee earned the wages in March but you cut the check in April, those wages belong on the second-quarter report.6Arizona Department of Economic Security. Reporting Wages – Completing the Reports
Filling Out Section A: Monthly Employment
Section A asks for the number of covered workers in each of the three months. For each month, enter the count of all full-time and part-time employees who worked during (or received pay subject to unemployment tax for) the payroll period that includes the 12th of that month.5Arizona Department of Economic Security. UC-018 – Unemployment Tax and Wage Report If you had no employees during a month’s payroll period, enter zero. Don’t leave the space blank. DES uses these numbers for labor-market statistics and will flag an incomplete form.
Filling Out Section B: Wage Listing
Section B is the employee-by-employee listing. For each person you paid during the quarter, enter three things: Social Security number, name (last name first), and total gross wages for the quarter.5Arizona Department of Economic Security. UC-018 – Unemployment Tax and Wage Report Put employees in either alphabetical order by last name or numerical order by Social Security number.6Arizona Department of Economic Security. Reporting Wages – Completing the Reports
If your workforce doesn’t fit on a single page, continue on additional sheets of plain white paper using the same column format, or use Form UC-020, the continuation sheet DES provides. Every page, including any continuation sheets, must show your employer name, account number, and the calendar quarter and year being reported.6Arizona Department of Economic Security. Reporting Wages – Completing the Reports Missing header information on a continuation page counts as an incomplete report and can draw a penalty.
Filling Out Section C: Calculating the Tax
Section C is the math. Arizona’s taxable wage base is $8,000 per employee for 2026, so you owe unemployment tax only on the first $8,000 each employee earns during the calendar year.7Arizona Department of Economic Security. 2026 Unemployment Insurance Tax Rate Chart The calculation runs in four steps:
- Line C1: enter the sum of all wages from Section B.
- Line C2: enter excess wages. For any employee whose year-to-date wages have already crossed $8,000, the portion above that threshold is excess. Total those amounts across all employees. Line C2 can never be larger than Line C1.8Arizona Department of Economic Security. Reporting Wages – Excess Wages
- Taxable wages: subtract Line C2 from Line C1.
- Tax due: multiply taxable wages by your assigned tax rate.
Tracking excess wages requires cumulative records across quarters. If you paid an employee $6,000 in the first quarter and $5,000 in the second, only $2,000 of that second-quarter figure is taxable. The remaining $3,000 pushes the employee past the annual $8,000 cap and counts as excess.
Quarterly Deadlines
The UC-018 is due on the last day of the month following the end of each quarter:1Arizona Department of Economic Security. A Guide to Unemployment Insurance Tax and Benefits
- First quarter (January through March): April 30
- Second quarter (April through June): July 31
- Third quarter (July through September): October 31
- Fourth quarter (October through December): January 31
When a due date lands on a weekend or state holiday, the deadline moves to the next business day. Not receiving a preprinted form in the mail does not excuse a late filing; Arizona’s administrative code is explicit on that.1Arizona Department of Economic Security. A Guide to Unemployment Insurance Tax and Benefits You file even if you paid no wages during the quarter. Just submit the form with zeros.
How to Submit
Online Through the Tax and Wage System
The fastest route is DES’s online Tax and Wage System at uitws.azdes.gov. Once you’re logged in, you can key each employee’s Social Security number, name, and quarterly wages directly into the system, or upload a comma-delimited file (.txt or .csv) with all the data at once.9Arizona Department of Economic Security. Arizona Unemployment Tax and Wage System – Filing Tax and Wage Reports The first time you use the system, you’ll enter all employee information from scratch. After that, it retains prior-quarter data, so you only update wages and add or remove people.
File upload is the practical choice once your headcount grows past a handful. Each line needs the Social Security number, first name, last name, and total quarterly wages, separated by commas. The system confirms receipt immediately.
Paper Filing by Mail
Mail the completed, signed UC-018 to:
Arizona Department of Economic Security
P.O. Box 52027, Mail Drop 5881
Phoenix, AZ 85072-20275Arizona Department of Economic Security. UC-018 – Unemployment Tax and Wage Report
Paper submissions don’t generate an instant receipt, so keep a copy of what you send and use a delivery method that gives you a postmark or tracking number.
What Late Filing Costs
Missing the deadline triggers a penalty of 0.1 percent of total wages paid during the quarter, with a minimum of $35 and a maximum of $200.10Arizona Legislature. Arizona Code 23-723 – Penalties for Failure to File Contribution and Wage Reports The penalty applies per delinquent report, so multiple missed quarters each carry their own charge. DES can waive the penalty for good cause, but you’ll need a reason beyond forgetting.
Unpaid taxes also accrue interest at 1 percent of the taxes due for each month or partial month the payment is late.11Arizona Department of Economic Security. Reporting Wages and Paying Taxes – Late Penalties A $500 tax bill left unpaid for three months picks up $15 in interest, on top of any filing penalty.
Fixing a Previously Filed Report
If you reported wages or taxes incorrectly on an earlier UC-018, submit a copy of that report with the corrections clearly marked and an explanation, or complete an Adjustment Form (UC-522).12Arizona Department of Economic Security. Reporting Wages – Corrections Fix the error on the quarter where it happened; never adjust a prior quarter on the current quarter’s report.
Do not enter a negative wage amount on a later report to offset an overpayment. DES’s system reads negatives as additional wages, which can result in a benefits overpayment to a claimant or extra taxes billed to you.12Arizona Department of Economic Security. Reporting Wages – Corrections To correct a name or Social Security number, send a letter with the old and corrected information, the affected quarters, and your employer account number to the Accounting Unit at P.O. Box 6028, Phoenix, AZ 85005-6028.
Records to Keep
The IRS requires employers to keep all employment tax records for at least four years after filing the fourth-quarter return for the year.13Internal Revenue Service. Employment Tax Recordkeeping Arizona law separately gives DES the authority to require reports and records it considers necessary for administering the unemployment insurance program.14Arizona Legislature. Arizona Code 23-722 – Reports of Employing Unit; Information Confidential Hold onto copies of every filed UC-018, any UC-522 correction forms, transmission confirmations from the online system, and the payroll records that back up the numbers.