Hamilton Sundstrand was an American globally active corporation that manufactured and supported aerospace and industrial products for worldwide markets. A subsidiary of United Technologies Corporation, it was headquartered in Windsor Locks, Connecticut. The company was formed from the merger of Hamilton Standard and Sundstrand Corporation in 1999. In 2012, Hamilton Sundstrand was merged with Goodrich Corporation to form UTC Aerospace Systems. In 2018, UTC Aerospace Systems and Rockwell Collins combined to form Collins Aerospace.

On June 10, 1999, Hamilton Standard and the Sundstrand Corp. were merged, forming Hamilton Sundstrand. Hamilton Sundstrand traces its roots to the founding of the Sundstrand Corp. in 1905 and Hamilton Standard in 1910. In early 2001, Claverham Ltd was sold to Hamilton Sundstrand.^{[citation needed]}

On 2 January 2008, Hamilton Sundstrand said it would commercialize the concentrated solar power tower technology and corresponding molten salt storage system developed by Rocketdyne through a new entity known as SolarReserve.

In 2012, Hamilton Sundstrand was merged with Goodrich Corporation to form UTC Aerospace Systems. In 2018, UTC merged UTC Aerospace Systems with Rockwell Collins to form Collins Aerospace.

Hamilton Sundstrand was among the largest global suppliers of technologically advanced aerospace and industrial products. Their three major businesses were Aircraft Systems (Commercial and Military), Industrial and Energy, and Space and Defense.

Hamilton Sundstrand supplied integrated systems solutions for military, commercial, regional, and corporate aircraft. These included:

The primary industrial products that were offered by HS included metering and specialty pumps, rotary screw air and gas compressors, pneumatic tools, dryers and filters, high-speed centrifugal pumps, integrally geared compressors, and sealless pumps.

Four separate companies that made up the industrial division of Hamilton Sundstrand were: