Hot tub warranties basically have 5 components:
Shell Structure - covers only 1 thing. It says that the shell will not leak. It does not cover leaks in the plumbing or even leaks through the shell around jet housings. Essentially this only says that the shell will not crack sufficiently to cause a leak. As you can see, you could have a pretty badly damaged shell and still not be covered by the "shell structure" warranty. This is the reason even some poorly made spas can have fairly lengthy shell structure warranties.
Shell Surface - this part of the warranty provides protection should your spa shell fade, delaminate, blister, have surface cracks, etc. With very few exceptions, it will always be considerably shorter than the shell structure warranty. Unfortunately some spa companies claim to have a shell surface warranty and then turn around and exclude some of the very issues that are shell surface issues.
Spa Structure - to our knowledge only 5 spa companies have a spa structure warranty. The reason: most spa companies continue to make their spa frames from wood!
Note: Some spa companies claim to have a "Structure Warranty" to give you the impression that they are covering the structure of the entire spa. However the fine print reveals that their structure warranty covers only the shell.
Plumbing - this covers exactly what it says. It says that your plumbing will not leak. Though a few companies exclude couplings at the pump and control pack, most do not. If you eliminate all the spa companies with various exclusions and prorated warranties, no spa company, other than Bullfrog Spas, has a plumbing warranty that exceeds 5 years.
Equipment - covers your control pack, pump, top-side controls, ozonator, etc. It will not cover items like, stereos, lighting, TV’s, etc. though these will likely have a much shorter warranty, typically only 1 year.
Note: It is common for mid-tier and low quality spa manufactures to try to escape their equipment warranties by telling you that you damaged your equipment by not maintaining your water chemistry properly. Again, we advise purchasing your hot tub only from the best companies in the industry.