You don't need to spend $1,000+ to get a real fish finder with GPS. These are the cheapest models we've reviewed that still deliver genuine CHIRP sonar and mapping, not a stripped-down toy, real prices confirmed at the retailer, not a manufacturer's suggested price.
Fish Finder Garmin Striker Cast
✓ No boat, mount, or wiring required, it's a self-contained castable unit
We're still finishing testing for this category, check out our Rankings in the meantime.
How low can you go without losing real functionality?
The cheapest real fish finders on this site still include genuine CHIRP sonar, you're not sacrificing sonar technology to save money, you're sacrificing screen size, side-imaging, and WiFi. The Garmin Striker Vivid 4cv keeps CHIRP and GPS at $199.99; going further down to the $139.99 Garmin Striker Cast drops the built-in screen entirely in exchange for portability and an even lower price.
What do you actually give up at this price?
Budget units in this range skip side-imaging sonar, WiFi connectivity, and larger high-resolution screens, real tradeoffs, not corner-cutting on core sonar accuracy. If side-scanning or forward-facing live sonar matters to you, expect to spend well above $500 to get it, see our full ranking above for those picks.