Assuming you’re talking about subterranean termites the soil around the foundation needs to be treated. 10 years ago I used Cascade Pest Control and was extremely happy with their service.
Just my mudroom was affected because it was an addition built with a cinderblock foundation, so I only had that area treated vs around the entire house. I don’t believe they give the 5-year guarantee if you don’t have the whole perimeter done though.
Make sure you don’t have standing water around the foundation and that you don’t have a woodpile anywhere near the house as that takes away their food and water sources for nesting.
I’ve used John from Adept Pest for rat issues. He’s amazing. I’m assuming he can deal with termites. If he can’t, he’ll be honest with you. Found him through WSB and other recommendations for his work. He saved us tons of money with a rat issue and tunneling into our crawl space. Had others tell me there was nothing we could do.
John at Adept Pest is AMAZING. Intelligent, prompt, reasonably priced, conservative alternatives to poison. The other pest control people I’ve dealt with were Neanderthals who wanted to set bait traps everywhere and drench the area with chemicals. One even told me that “rats aren’t animals”. You can’t go wrong with John; search the WSB and you’ll find truckloads of recommedations for him.