I'm a consulting civil engineer in California. Each of the three companies I have worked for has given automatic promotions and salary increases for obtaining professional licensure. When I got my license way back in 1983 I got an additional $100/month. I don't know what it is now. I hope it's more.
It works something like this:
-- Obtaining a license earns an automatic promotion to a new classification, say from "Assistant Engineer" to "Associate Civil Engineer" (as an aside, the assistant engineer can't be called an Assistant CIVIL Engineer because the title of "Civil Engineer" is legally protected).
-- With a license, the newly minted Civil Engineer can now take on real professional responsibilities, justifying a higher salary, though the rate they take them on varies by individual and circumstance. With a license comes the ability to manage projects (starting small, then working up) and the ability to stamp and sign documents (after rigorous QC review, of course). We can now also include the newly minted Civil Engineer in proposals for new work. The "advertising" benefit to the company starts small, but increases with experience.
-- The new classification carries a higher billing rate and the higher billing rate can handle a higher salary while still maintaining profitability. In fact, the company benefits too because the individual's Net Labor Multiplier (i.e. the ratio of Billing Rate to Salary) typically increases at the start of each promotion cycle. I used this fact one time to negotiate a higher salary increase that I was first offered and I still left the company with a higher NLM than I was leaving behind. IIRC, I was at a NLM of 2.95 (our target was around 3.00), the salary I was offered produced a NLM of 3.50, and I obtained a salary with a NLM of 3.30. I came out good without overplaying my hand and the company made out even better.
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