Texas splits late renewal into two windows, and the second one is the expensive one.
There is a line at ninety days. On one side a late renewal is an annoyance. On the other it is a bill.
The two tiers
The board prices late renewal in two bands: expired under 90 days, and expired over 90 days. The second band costs more. On the RMP designation, for example, late renewal runs $150 under 90 days and $300 over 90 days, on top of the normal renewal.
Your own license type has its own numbers. Look yours up rather than assuming.
The part that is not about money
An expired license is not a grace period. It is an expired license. Work performed on it is work performed without a license, and if you are the responsible master plumber, everything your crew does runs through your number.
That is not a late fee problem. That is a different category of problem, and it is the reason to care about the date rather than the dollar amount.
How to never see either band
Do the six hours early in your renewal window instead of late. The hours are the only part of renewing that takes a day, and they are the only part you cannot do at 11 PM the night before. Everything after them is a form.
Put your expiration date in your phone with a ninety day warning. That is the entire system.
Primary sources
Rules change and this page is dated. Confirm anything that affects your license against the board before you act on it.
Told straight, once
Status: the Texas Plumber CE provider and course applications are with the Texas State Board of Plumbing Examiners. Nothing is for sale until the board issues approval.
One email when a Texas plumbing rule actually moves. One when registration opens. Nothing else.