Sen. Tommy Williams, R-The Woodlands, announced his official resignation from the Texas Senate District 4 after 10 years serving the position and 16 total years served on the Texas Legislature.

"Serving the people of Southeast Texas for almost 17 years in the Texas House and Senate has been a great privilege and an honor," Williams said in a letter to Gov. Rick Perry. "Nothing, save my faith and family, has meant more to me."

Weeks after announcing he would not return for the 2015 Legislative Session, Williams made his resignation official Oct. 25 in letters to Perry, Lt. Gov. David Dewhurst and in a message to his constituents.

"I have enjoyed representing you in both the Texas House and Texas Senate, but it's time for me now to move on," he said to his constituents. "I do so filled with extraordinary gratitude for the opportunity, and incredible good fortune I've had to have so many great people working for me. Their support has enabled me to serve my constituents and the State of Texas."

In the message, Williams said his resignation would cause Perry to call a special election to fill the unexpired portion of his term, which runs through 2016.

The race to fill the position has become crowded since he made his initial announcement, with Rep. Steve Toth, R-The Woodlands, Rep. Brandon Creighton, R-Conroe, and Woodlands Township Director Gordy Bunch all announcing plans to run for the empty seat. Township Chairman Bruce Tough and Director Nelda Blair would neither confirm or deny their intentions to run for the position.

The potential candidates said an election would likely be held at the next uniform election date in May. The election would not require a primary, but would rather allow candidates from all political parties to run for the position. The winning candidate would need to earn 50 percent of the votes, or a runoff election would be required to name the winner.

Williams said much of his Senate staff will continue to help serve the district until a successor is chosen. In a press release, Williams, 56, said he and his wife, Marsha, are "looking forward to new opportunities and spending more time with their family."

A certified public accountant, Williams was the chairman of the Senate Finance Committee over the last legislation session and helped shape the 2014-15 budget, calling the experience the "highlight of his legislative career." Williams joined the Texas Senate in 2003 after three terms served on the Texas House of Representatives.

"I wish I could thank each of you for the opportunity you've given me to represent our region in Austin," he said. "You placed your trust and confidence in me, and it is something I will always remember. I took on this responsibility with enthusiasm, and it has truly been my greatest honor."