Louisiana Form L-1 is the Employer’s Return of Louisiana Withholding Tax, filed through the Louisiana Taxpayer Access Point (LaTAP) on a quarterly, monthly, or semi-monthly schedule the Department of Revenue assigns based on how much tax you withhold each month. The form itself has four lines: tax withheld, penalty, interest, and total remittance.
Who Has to File
Any employer that deducts and withholds Louisiana state income tax from employee wages must file an L-1 for every reporting period. Louisiana Revised Statute 47:114 directs every such employer to submit a return to the secretary of the Department of Revenue on a prescribed form and pay the tax shown due.1Louisiana State Legislature. Louisiana Code 47:114 – Returns and Payment of Tax This covers Louisiana-based businesses and out-of-state companies with employees working in the state. One employee whose wages are subject to Louisiana withholding is enough to trigger the obligation.
You need a Louisiana Revenue Account Number before you can file. New employers register through the department’s online business registration portal or by mailing Form R-16019 to the Louisiana Department of Revenue, PO Box 201, Baton Rouge, LA 70821-0201.2Louisiana Department of Revenue. How Do I Register for Withholding Tax? Electronic applications process faster than paper.
Filing Frequency and Due Dates
The department sets your frequency based on monthly withholding. The three tiers:3Louisiana Department of Revenue. How Often Must I Submit My Withholding Tax?
- Quarterly, for employers withholding less than $500 per month. Returns are due the last day of the month following each calendar quarter: April 30, July 31, October 31, and January 31.
- Monthly, for employers withholding at least $500 but less than $5,000 per month. Returns are due the last day of the following month.
- Semi-monthly, for employers withholding $5,000 or more per month. Payments must be made by electronic funds transfer. For wages paid the 1st through 15th, the return is due the last day of that same month. For wages paid the 16th through month-end, it is due the 15th of the following month.4Louisiana Department of Revenue. Notice of Intent – Revenue
If a due date falls on a weekend or holiday, the return is due the next business day. The department can also grant “occasional” filing status to employers who have filed for two consecutive years, had withholding in no more than two quarters of any year, and never exceeded $1,500 in withholding for any quarter. Occasional filers submit only for quarters in which they actually withheld tax.5Louisiana Department of Revenue. Instructions for Employer’s Return of Louisiana Withholding Tax Form L-1
Watch your monthly totals. If your liability crosses a threshold, the department can move you to a more frequent schedule.
Completing the Four Lines
Form L-1 is short. Here is what each line asks for:5Louisiana Department of Revenue. Instructions for Employer’s Return of Louisiana Withholding Tax Form L-1
- Line 1, Louisiana income tax withheld. Enter the total state income tax you withheld, or were required to withhold, from all employees’ wages during the period. State income tax only. Do not include federal withholding, Social Security, Medicare, or insurance premiums.
- Line 2, Penalty. If you are filing or paying late, calculate the penalty yourself and enter it here. The rate is 5% of the tax due for each 30-day period or fraction thereof, capped at 25%.
- Line 3, Interest. If payment is late, calculate interest using the rates on the department’s Tax Interest Rate Schedule (Form R-1111) and enter the amount.
- Line 4, Total remittance. Add Lines 1, 2, and 3. This is what you pay.
Have your Louisiana Revenue Account Number ready, along with the period ending date — the last day of the quarter, month, or semi-monthly period you are reporting.
One quirk about electronic payments. If you make an EFT or credit card payment for tax only, with no penalty or interest, the payment itself serves as the return and no separate L-1 is required. But if the payment includes penalty or interest, you must file the L-1 to break out those amounts. Otherwise the department treats the entire payment as tax due.5Louisiana Department of Revenue. Instructions for Employer’s Return of Louisiana Withholding Tax Form L-1
How to Submit and Pay
Most employers file through LaTAP at latap.revenue.louisiana.gov.6Louisiana Department of Revenue. File and Pay Online Approved third-party payroll software is also an option.7Louisiana Department of Revenue. What Are My Filing Options for Form L-1? Create a secure LaTAP account, log in, enter your figures into the online form, and submit. The system returns a confirmation number. Save it as proof of timely filing.
Paper filing is still available if you are not required to file electronically.7Louisiana Department of Revenue. What Are My Filing Options for Form L-1? Semi-monthly filers must remit by electronic funds transfer, so paper is not practical at that tier.3Louisiana Department of Revenue. How Often Must I Submit My Withholding Tax? If you mail a paper return, send a check or money order, not cash, and write your Revenue Account Number on the payment.
Through LaTAP, ACH debit from a linked bank account carries no convenience fee.8Louisiana Department of Revenue. Application for Louisiana Revenue Account Number Credit card payments go through a third-party processor and carry a convenience fee charged by that processor.9Louisiana Department of Revenue. Credit Card Payments
If You File or Pay Late
Late filing and late payment each carry a penalty of 5% of the tax owed for every 30-day period, or fraction of one, that the return or payment is delinquent. The penalty tops out at 25%.10Louisiana State Legislature. Louisiana Code 47:1602 – Penalty for Failure to Make Timely Return At three months late you already owe 15% on top of the tax.
Interest is separate and runs from the original due date until the tax is paid in full. Louisiana sets the rate at the judicial interest rate plus three percentage points.11Louisiana State Legislature. Louisiana Code 47:1601 – Interest on Unpaid Taxes The 2026 judicial rate is 7.50%,12Louisiana Office of Financial Institutions. Judicial Interest Rates which puts the 2026 underpayment interest rate at 10.50% annually, or 0.875% per month.13Louisiana Department of Revenue. R-1111 Interest Rate Schedule The rate resets each calendar year, so check the current R-1111 schedule before computing a late return.
Penalty and interest are self-assessed on Lines 2 and 3. The department’s system flags missing returns automatically, so ignoring a delinquent filing invites an assessment and collection action rather than making it go away.
If You Use a Payroll Service
Outsourcing payroll to a third party that handles withholding calculations, L-1 filings, and tax deposits is common and operationally fine. It does not shift legal responsibility. If your payroll company fails to remit withholding taxes on time, or at all, you remain liable for the unpaid tax plus penalties and interest, even if you had no reason to suspect a problem.
Individuals who control company finances — anyone with signature authority on payroll accounts, or who serves as a corporate officer — can also be held personally liable for unpaid withholding taxes. Verify deposits independently by logging into LaTAP and confirming your payments are posting as expected.