25. Suffolk County, New York
> Total population: 1,526,344
> 1-yr. population change: +0.1% (+2,245 people)
> Largest place in county: Brentwood

Source: benedek / E+ via Getty Images
24. Philadelphia County, Pennsylvania
> Total population: 1,576,251
> 1-yr. population change: -1.5% (-24,754 people)
> Largest place in county: Philadelphia

Source: GCShutter / E+ via Getty Images
23. New York County, New York
> Total population: 1,576,876
> 1-yr. population change: -6.6% (-110,958 people)
> Largest place in county: Manhattan (NYC)

Source: Brandon Williams / iStock via Getty Images
22. Sacramento County, California
> Total population: 1,588,921
> 1-yr. population change: +0.2% (+2,680 people)
> Largest place in county: Sacramento

Source: DenisTangneyJr / iStock via Getty Images
21. Middlesex County, Massachusetts
> Total population: 1,614,742
> 1-yr. population change: -0.9% (-14,680 people)
> Largest place in county: Lowell
Sponsored: Tips for Investing
A financial advisor can help you understand the advantages and disadvantages of investment properties. Finding a qualified financial advisor doesn’t have to be hard. SmartAsset’s free tool matches you with up to three financial advisors who serve your area, and you can interview your advisor matches at no cost to decide which one is right for you. If you’re ready to find an advisor who can help you achieve your financial goals, get started now.
Investing in real estate can diversify your portfolio. But expanding your horizons may add additional costs. If you’re an investor looking to minimize expenses, consider checking out online brokerages. They often offer low investment fees, helping you maximize your profit.