Phone scams claimed more than $25.4 billion from American adults in a single year , with 21% of the population — over 56 million people — falling victim at least once, according to Truecaller's US Spam & Scam Report. The calls sound real. The numbers look familiar. And the tactics are getting more convincing by the month. Knowing how to spot suspicious calls and verify unknown numbers before engaging is now a basic personal finance skill, not a niche concern.