Calculate your cost basis
quickly and easily.

During tax time, shareholders are burdened with calculating their cost basis in order to report their capital gains to the IRS. This can be a very difficult and time-consuming process even for professional tax preparers. There is an easier way.

Otter Tail Corporation has partnered with NetWorth Services and Depository Trust & Clearing Corporation (DTCC) to provide you access to the AccuBasis Cost system. The AccuBasis Cost system will automatically calculate your cost basis including any shares you acquired through dividend reinvestment or stock splits.

To use the AccuBasis system, you will need:

• Your purchase or acquisition dates
• Your number of shares acquired and sold
• Your sale dates

Within seconds, you will have your cost basis, gain/loss and sale proceeds as well as the current status of your investment. The AccuBasis system will also provide you with supporting documentation for your records.

To access the AccuBasis system, please go to www.accubasis.com or select the link on this page to go directly to the site. Please note that there is a transaction fee to use this service which is posted on the AccuBasis web site.

If you have any questions or problems using the AccuBasis system, please call the 24/7 Customer Care Call Center at 1-888-55-BASIS (1-888-552-2747) or use the live Web Chat Service located on the Help button once you have logged on to the system.

For Otter Tail Corporation employees who are enrolled in the company's ESPP plan, please note that this service would not be applicable. You will need to use the price information that was sent to you with your statements to calculate your cost basis.