The close will cause a major delay for some.
"One of the big effects is that mail will go from a 1 to 3 day delivery," said Florence's United Postal Workers President Isaac Nixon.
Isaac Nixon said this change will occur in January because that's when the Florence Post Office will no longer perform mail processing.
Instead mail will be processed in Columbia.
"The mail is circulated through various machines and then sent back to the post office to be delivered," said Nixon.
"It will slow our mail down too much not only in Florence, but also the beach," said Pat Gibson Hye-Moore.
A USPS spokesperson said the soon to come change will only make our mail delayed by a couple of hours, not days like Nixon said.
But Nixon and others are fighting to get Florence's processing center running again at full capacity.
On Wednesday, Pat- Gibson Hye-Moore took a letter to Congressman Tom Rice's office and requested a town hall meeting.
As for the 150 people whose jobs were impacted by this downsize, those who did not retire were able to apply for other jobs within the company.
USPS said processing centers around the US are being consolidated because the system was built to handle 300 billion pieces of mail. They are only processing 150 billion pieces.
The company said the Internet has partially replaced the need to send First Class mail.