Seth Thomas

Click here to review our Seth Thomas conversion chart.

Seth Thomas movement codes start with the letter "A” followed by a set of three numbers, a dash (-) and three additional numbers, i.e. A123 - 123. 

Seth Thomas is recognized as one of the most respected clock brands in the world. Seth Thomas gained an impeccable reputation for producing masterfully crafted grandfather clocks. The company is also known for designing and producing some of the nation’s most renowned tower clocks, including the tower clock at Grand Central Station in New York.

Seth Thomas was born in Connecticut in 1785. He went to work for clockmaker Eli Terry in 1807 and eventually bought Terry’s factory in 1810. It was in 1853, after many years of producing wooden and brass clock movements, Seth Thomas incorporated Seth Thomas Clock Company so the business would outlive him. Thomas died in 1859 and left his company in the hands of his sons. They continued to expand the business and experimented with many new clock styles.

After several mergers with other clock companies, the manufacturing of Seth Thomas clocks ceased in 2001. You know you own a Seth Thomas clock by the date code stamped in ink on the back or bottom of the clock case. This is typical of the clocks produced from 1881 to 1918. Characteristically, the year is printed in reverse, followed by a letter “A” through “L” representing each month. For example, April 1897 would appear as “7981 D.”

Original Seth Thomas replacement movements are no longer available. However, Dakota Clock Works offers a complete selection of nearly identical Hermle replacement movements. These movements will work perfectly in your Seth Thomas clock. Our downloadable PDF chart contains information to convert the Seth Thomas code on your existing movement to the appropriate Hermle replacement model number.

The fool-proof way to find the precise replacement movement for your grandmother, grandfather, wall or mantle clock is to answer “The Big Four.” 

Review the downloadable PDF chart. Once you have identified your Hermle replacement model number, proceed to the Contact-Order Form. Copy the model number into the specified field and supply your contact information.

We also sell replacement parts and accessories for Seth Thomas clocks. Use the above navigation links and drop-down menus to locate your desired product(s). If you are unable to find what you need, call toll-free 1-877-425-4879 and let us help you! Our comprehensive inventory limits our ability to post every item online, thus, we encourage your call!

Dakota Clock Works offers the "Triple Advantage”:

• Free support after the sale
• Comprehensive installation instructions
• Full, one-year warranty

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