When the mortgage has been paid and it can be verified that the funds have cleared, it is no longer necessary to keep the mortgage statement. The statement shows only the amount billed, while other valuable information, such as interest and deductions, are only sent once per year.
Keeping statements from a mortgage company and comparing them could help a consumer discover errors from one month till the next. Online statements could do the same.
Reviewing and keeping mortgage statements either in an electronic format or in paper format in a file make sense. The information on the statements, however, is only good for a period of one year. Once the mortgage tax paperwork goes out in January, the prior year's data is no longer valid, thus there is no reason to keep it beyond that point.