You'll get Flex Mode, not full dual-channel.

Yes, but with a catch. If your laptop has one soldered stick and one socketed slot, most modern chips support “Flex Mode” — the first 16GB (8+8) will run dual-channel, and the remaining 8GB of the 16GB stick will run single-channel.

So 24GB total: 16GB dual, 8GB single. For most everyday tasks, you won’t notice a difference. For memory-intensive work like video editing or large VMs, the mismatched capacity means slightly slower access to that last 8GB. It’s still better than having only 8GB or using only the soldered stick.

The real question is whether your motherboard supports it. Most Intel and AMD laptops from the last 5–6 years do. If in doubt, check your laptop’s spec sheet for “Flex Mode” or “asymmetric dual channel.”

It’s not ideal, but it works. Future You will appreciate having 24GB over 8GB or 16GB.