Best Serial Adapters Under $200 (2026)

We ranked products under $200 by a composite value score that weights chipset reliability, connector variety (DB9/DB15), user ratings, and practical features like multi‑port support and included cases

Top Picks

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    USB to RS232 adapter with FTDI chipset

    USB to RS232 adapter with FTDI chipset

    StarTech • ★ 4.1/5 • Mid-Range

    USB to serial RS232 adapter converting USB to a null modem DB9 port. Compatible with Windows, Mac, and Linux. Customers praise plug-and-play setup and reliable FTDI FT232R chip

    • FTDI-based reliability
    • USB to RS232 null modem capability
    • cross-platform compatibility
    Check current price on Amazon →
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    DB9 Male Breakout Connector with Case

    DB9 Male Breakout Connector with Case

    ANMBEST • ★ 4.0/5 • Budget

    DB9 solderless breakout board for RS232 serial connections. Provides easy wiring and durable joints for reliable signal transfer. Customers note solid quality and ease of use, though some find it bulky

    • solderless terminal adapter
    • case with long bolts
    • pure copper plated joints
    Check current price on Amazon →
  4. 4
    Gearmo 4 Port USB to RS232 Adapter with FTDI

    Gearmo 4 Port USB to RS232 Adapter with FTDI

    Gearmo • ★ 3.9/5 • Mid-Range

    USB to RS-232 adapter with four ports and FTDI chipset for cross-platform use. Plug-and-play with COM port retention for stable serial connections. Customers note reliable Linux compatibility and solid build quality

    • multiplatform compatibility
    • four COM ports
    • no external power required
    Check current price on Amazon →
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Buying Guide

Choose the right interface

Match the adapter to the port you need—USB-to-RS232 for modern PCs, DB9 or DB15 breakout boards for direct D‑sub wiring and pin access

Prefer verified chipsets

Opt for adapters using known chipsets like FTDI for wider driver support and predictable compatibility with Windows, macOS, and Linux

Check port count and form factor

Select single-port dongles for occasional use or multi-port USB adapters when connecting several serial devices simultaneously

Look for breakout convenience

Solderless DB9/DB15 breakout boards and connector sets simplify prototyping and maintenance by exposing all D‑sub pins in an organized case

Evaluate build and connection quality

Metal-backed connectors, strain relief on USB cables, and clear labeling reduce intermittent connections and simplify troubleshooting