X0306 4 2019-11-18 0 0001050377 PC CONNECTION INC CNXN 0001188266 MCGRATH TIMOTHY J 730 MILFORD ROAD MERRIMACK NH 03054 0 1 0 0 President & CEO Common Stock 2019-11-18 4 S 0 12845 51.09 D 244207 D Common Stock 2019-11-19 4 S 0 9686 51.48 D 234521 D Common Stock 2019-11-20 4 S 0 17469 51.36 D 217052 D The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 1, 2019. The shares were sold in multiple transactions on November 18, 2019 at an actual price ranging from $50.59 to $51.55 per share. The price reported reflects the weighted average sale price for the transactions. The reporting person undertakes to provide upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price. The shares were sold in multiple transactions on November 19, 2019 at an actual price ranging from $51.25 to $51.75 per share. The price reported reflects the weighted average sale price for the transactions. The reporting person undertakes to provide upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price. The shares were sold in multiple transactions on November 20, 2019 at an actual price ranging from $50.41 to $51.85 per share. The price reported reflects the weighted average sale price for the transactions. The reporting person undertakes to provide upon request by SEC staff, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price. /s/ Timothy J. McGrath 2019-11-20