What is IRP?

You may hear the International Registration Plan referred to as IRP.

The purpose of the International Registration Plan (IRP) is to promote and encourage the fullest use of highways by authorizing the proportional registration of vehicle fleets and the recognition of vehicles proportionally registered in other jurisdictions to aid in economic and social development and growth of all jurisdictions.

In accordance with the IRP, an interstate carrier is only required to submit an application with the jurisdiction in which it’s based. The base jurisdiction issues the IRP apportioned license plate and IRP cab card. Since the IRP cab card will list all jurisdictions in which you have paid registration fees, it is the only vehicle registration required to operate interstate or intrastate in IRP jurisdictions. However, all other requirements pertaining to fuel or any other tax must be in compliance before you enter each state.

Apportioned vehicles are defined as any vehicle used or maintained primarily for the transportation of property and is one of the following:

  • A power unit having two axles and a Gross Vehicle Weight (GVW) or registered GVW in excess of 26,000 pounds or 11,793.401 kilograms.
  • A power unit having three or more axles regardless of weight.
  • Used in combination, when the weight of such combination exceeds 26,000 pounds or 11,793.401 kilograms.

Vehicles, or combinations thereof, with a GVW or registered GVW of 26,000 pounds or less and two-axle vehicles may be proportionally registered at the option of the registrant.

In some circumstances, a carrier may operate under another motor carrier authority and USDOT number.  An  Operational Lease (SCDMV Form IRP-9). must be completed by both parties and submitted to Motor Carrier Services at the time of the IRP Renewal or if you change the company that you are leasing under.

Authorized Users for IRP Accounts

A Power of Attorney Authorization Form (SCDMV Form MC-25 ) form must be on file for anyone other than the account holder to conduct business in an IRP Account. This form must also be on file for anyone other than the account holder to call and ask questions about the account. 

Cab Card

Your International Registration Plan (IRP) cab card will show all IRP states and Canadian provinces. Your  IRP fees are calculated based on your June-July "reporting period" distances.

If you are a new carrier without a reporting period history, you will  pay fees based on the South Carolina Average Per Vehicle Distance Chart (SCDMV Form IRP-APVD-2018).

You are able to operate in any IRP jurisdiction without adding a jurisdiction or buying a trip permit. For each IRP renewal, fees are charged based on the fleet’s "reporting period" distance.

IRP Reminders

Motor Carrier Services (MCS) emails a notification when it is time to renew IRP registration. To ensure proper reminders you must provide MCS with an updated your email address. 

IRP (Celtic) Fee Estimator

The IRP (Celtic) Fee Estimator is a tool to help you estimate the fees associated with registering an apportioned vehicle based on various factors, including the distance associated with the jurisdictions of travel. This estimation is based on the estimated cost to register one new vehicle in IRP. This estimate does not include the base jurisdiction administrative fees or base jurisdiction non apportioned fees. Please contact (803)896-3870 or MCSHQ@scdmv.net for more information.

Celtic Fee Estimator - International Registration Plan, Inc. (irponline.org)

Web Transactions

You may process IRP web transactions online via the MCS Portal. 


If you do not have access to the MCS Portal, you may mail or email a completed Motor Carrier Web Entry Access (SCDMV Form MC-26) to the following:

Motor Carrier Services
P.O. Box 1498
Blythewood, SC 29016-0027

Email: MCSHQ@scdmv.net

Heavy Vehicle Use Tax

International Registration Plan (IRP) Registrants must show a Heavy Vehicle Use Tax (HVUT) return, Schedule 1 2290 (IRS Form 2290), validated by the IRS for the current tax year or a copy of the form accompanied by a photocopy of the canceled check (front and back) used to pay the tax.

  • The owner of any vehicle with a declared gross vehicle weight (GVW) of 55,000 pounds or more, regardless of the type of vehicle, must provide Schedule 1 tax paid receipt from the Internal Revenue Service.
  • You should file HVUT returns with the IRS from July 1 to August 31 for any vehicle currently licensed.
  • Customers who register 25 or more vehicles for any taxable period are required to electronically file their HVUT tax return with the IRS. If you acquire additional vehicles after the initial filing of the tax return, you do not have to electronically file the return for those vehicles. The SCDMV does not accept tax returns if you’re registering 25 or more vehicles.
  • The HVUT Return (IRS Form 2290) must be filed by the last day of the month, following the month of the first use.
    • For example, if an individual uses a taxable vehicle on a public highway by driving it home from the dealership on July 2, 2018, after purchasing it. The individual must file IRS Form 2290 by August 31, 2018, for the period beginning July 1, 2018. For more information, visit https://www.irs.gov/pub/irs-pdf/i2290.pdf and view page 3.

For further information on vehicles exempt from the HVUT go to www.irs.gov.


Credentials for the registration year should be on your vehicle no later than midnight of the last day of your expiration month. License plates must be mounted on the front of the power unit and the back of trailers and semi-trailers. The original cab card must be available for inspection by appropriate enforcement personnel; copies are not acceptable.

Adding or Deleting Vehicles

When adding or deleting a vehicle to or from a fleet, it will be necessary to file a Supplemental Application (SCDMV Form Schedule C) in the same manner as the original.

Registration fees may be transferred from the deleted vehicle to the added vehicle, providing it is a vehicle of the same type and registered in the same name. You must pay a $10 transfer fee to South Carolina, plus any fees that may be due to another jurisdiction. Not every IRP member jurisdiction allows for registration fee transfers, therefore, you will be charged a prorated registration fee for those states.

In cases where a deleted vehicle is not being replaced, the registrant is required to submit a completed Schedule C to Motor Carrier Services (MCS) within 30 days. The IRP cab card and license plate must also be returned, where it will remain on file until expiration. Should a replacement vehicle be purchased prior to expiration of the apportioned license and you wish to transfer the registration fees, you should contact MCS for assistance.

Weight Increase

Vehicle weights will not be decreased during the license year. Weight decreases can only be made at license renewal time.

If you decide to increase your registered weight for any member jurisdiction, you must file a Supplemental Application (SCDMV Form Schedule C) with the SCDMV. Additional fees will be calculated for the increase in weight for the remaining portion of the registration year.


Mileage Reporting Tips

When renewing your IRP account, be sure to report accurate miles during the reporting period. A common mistake seen during audits of IRP/IFTA renewal packets is unrealistic mileage reports. Carriers cannot estimate distance for jurisdictions from the actual distance the fleet accumulated in the previous reporting period.

If a carrier is filing a IRP Renewal and receives a hard stop stating Unrealistic Distance, the carrier must bring their distance records into a motor carrier services field office for a clerk to review their records.