Skip to content


What is a commercial scale?

In Minnesota, a commercial scale is defined as any scale used to buy or sell commodities or services for which the price is determined by weight. The Weights and Measures Division inspects commercial scales. If a scale passes inspection, the investigator attaches a dated approval sticker to the scale. The investigator rejects any commercial scale that is not accurate, not of commercial quality, or not suitable for its intended use.

How do I know if I need to have a commercial quality scale?

You must have a commercial quality scale if you buy or sell a commodity or service by weight. For example, you must have a commercial quality scale to sell candy, produce, nails, beads, seed, bait, oxygen, or other commodities by weight. Your scale must also be of commercial quality if it prints price labels for meat, deli, bakery, produce, or other items; if it is used to buy metal, jewels, or any other commodity by weight; or if it is a shipping or laundry scale, or is used to determine the price of any other service.

How do I know if my scale is commercial quality?

Any commercial scale manufactured after January 1, 1986 must be labeled Class III if it is commercial quality. It will have an identification plate with the serial number, the manufacturer's name, a model number, maximum capacity, number of measurement divisions, and size of the smallest measurement.

Commercial quality scales manufactured before January 1, 1986 may be labeled class III and have an identification plate as described above. A scale manufactured before 1986 which has no class marking is commercial quality if it has a manufacturer's name, serial number, maximum capacity listing, and measurement division size printed on it.

To be of commercial quality, mechanical scales must have a zero which requires a tool to adjust and electronic scales must have a means for sealing the calibration mechanism.

Bathroom scales, baby scales, scales marked Not Legal for Trade, and mechanical scales with thumbscrew zeros or other zeroing mechanisms which can be adjusted without a tool, are not commercial quality scales and must not be used for commercial transactions in Minnesota.

How do I know if my scale is suitable for its intended use?

A scale is suitable for its intended use if the minimum load which will be weighed on it is 20 measurement divisions or more. A scale whose smallest division is 0.05 lb. is suitable for minimum loads of 1 lb. or more. US Department of Agriculture requires .01 lb. or smaller divisions for meat scales with label printers. Mechanical meat scales may have divisions no larger than 1 ounce. For most other applications, scale divisions of 1 ounce, or .01 lb. are adequate.

When will my scale be tested?

The company which sells you the scale will notify the Weights and Measures Division and an investigator will test the scale within 30 days of purchase. If you buy a scale from a private party, you are responsible for notifying the Weights and Measures Division of the purchase, and you must not use the scale until it has been approved. Do not assume that a scale which has last year's approval sticker will pass inspection. Have a reputable scale company examine the scale before you buy it, or make an agreement with the seller before the sale about what will happen if the scale is rejected.

After the initial inspection, a commercial grocery, food or hardware scale may be inspected every 3 years or in response to a consumer complaint. All other commercial scales may be tested annually or in response to a consumer complaint.

What happens if my scale is rejected?

If your scale is rejected, the investigator will attach a tag to the scale and give you a rejection report explaining why it was rejected.

If the investigator attaches a yellow tag, you may continue to use the scale, but you must make the required repairs within 30 days. If the investigator attaches a red tag, you must not use the scale until it has been repaired. If you have the scale repaired by a company certified by the Weights and Measures Division, the technician will remove the tag and notify the investigator that the repairs were completed. You may use the scale as soon as the tag is removed. If you repair the scale yourself, you must fill out the appropriate portion of the rejection report and mail it to the Weights and Measures Division. If the scale was red-tagged and you repaired it yourself, you must not use it until the investigator has returned and removed the tag. If you do not repair a yellow-tagged scale, you must remove it from service after 30 days. Failure to do so could result in the confiscation of your scale.

In some cases, a scale will be rejected because it is not suitable for its intended use, or because it is not a commercial quality scale. Such scales will be red-tagged and removed from service. You must replace such a scale with a commercial quality scale suitable for its intended use. If you continue to use a scale which is not suitable or which is not commercial quality, the scale may be confiscated.

Who should I contact if I have further questions?

The Weights and Measures Division employees are happy to answer any questions you have about commercial scales. Please direct your requests to the Weights and Measures Division.

Minnesota Department of Commerce, Weights and Measures Division
14305 Southcross Drive #150
Burnsville, MN 55306
Phone: 651-539-1555
FAX: 952-435-4040
TTY: 952-435-4045