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The reduction of the yield of subsequent crops caused by soil compaction when harvesting canning peas, and the economic consequences of this, are estimated. Calculations are made for the harvesters used in Sweden today and for possible alternative harvesters. The calculations are based on data from a region where a total of 6.800 ha of canning peas are grown annually, mainly on sandy loam soils. A computer model is used based on driving distance of the machines, load and tire inflation pressure for individual axles, clay and moisture content of the soils, and the harvest value of subsequent crops. The most influential factor was the soil moisture content. Other significant factors, in order of importance, were the weight of the harvester, the driving distance, the clay content and the tire inflation pressure. For the harvester used today (FMC 125) the average crop yield reduction of subsequent crops was estimated to be 2.1 % of an annual yield. This corresponds to a compaction cost of 188 Skr/ha. The alternative with the least compaction cost (112 Skr/ha) was FMC 979 with widened pick-up and wide, lowpressure tires. When comparing these two alternatives the difference in compaction cost for the whole canning-pea acreage in the region is estimated to be 500.000 Skr/year, which no doubt compensates for the extra costs incurred in reducing soil compaction.