Devices and methods for withdrawing bodily fluid from a patient are disclosed herein. A handheld device configured in accordance with the present technology can include a housing having an opening, a skin-piercing assembly located at least partially within the housing, and an actuator movable relative to the housing along a deployment direction. The skin-piercing assembly can include a skin-piercing feature and a biasing member. The biasing member can be coupled to the skin-piercing feature to bias the skin-piercing feature along the deployment direction. Movement of the actuator along the deployment direction to a predetermined position can increase a load on the biasing member to at least a partially loaded state. Movement of the actuator along the deployment direction beyond the predetermined position can release the load on the biasing member so that the biasing member actively drives the skin-piercing feature along the deployment direction.
