A split and an overlay are different
561 was created from 407 in 1996. In 2002, the Treasure Coast separated into the 772 region. That was a geographic split, rather than two codes sharing one territory.
728 overlays the Palm Beach County region served by 561, with assignments beginning March 10, 2023. Existing 561 numbers stayed the same.
Source: Florida PSC: numbering history ↗
What the overlay means for a business
561 and 728 serve the same region and require ten-digit local dialing. The introduction of 728 did not itself change call prices or local calling areas.
A preference for 561 is a branding choice. It does not purchase better carrier service, and 728 is not less local to the overlay region.
Make your real location clear
The area code cannot distinguish a Palm Beach appointment from a Boca Raton office or a Delray business. Publish the actual town, address, or service area where that matters.
A caller’s number also does not prove current location. Check exact-number eligibility with the intended provider before purchasing a number for your business.