Not recommended, because some solder will wick down to the other side and the component on top will not solder correctly.
- Use capped
- Filled vias when doing via-in-pad to stop the solder draining away.
Remark: Before designing via-in-pad, don’t forget to talk to your PCB fabricator to find out what their capabilities are, and how much extra this costs.
Read More: What is PCB Via