The vehicle will carry two Earth-imaging Dove satellites for Planet and two Lemur-2 satellites from Spire for weather mapping and ship tracking.
Rocket Lab founder and chief executive Peter Beck said carrying a test payload marked a significant milestone for the Electron programme, enabling Rocket Lab to gather crucial data and test systems for the deployment stage of a mission.
"We're thrilled with Electron's performance in the first test flight and now we're eager to test the next crucial step - payload deployment," he said.
"No major changes to the launch vehicle hardware have been required, the third-party error that meant we didn't make orbit has been corrected and we're focusing on the six Electron vehicles in production right now."
The first test launch had to be terminated before it reached orbit because of an issue with an independent contractor's ground equipment.
Beck said the company was still operating in a test phase, and could expect a few scrubs during the second test-flight attempt.
"We're incredibly excited about carrying Planet and Spire payloads on Electron. The data these companies gather has an increasingly significant role to play in how we understand our planet and better manage it," he said.
Planet senior director of launch Mike Safyanat said it was fitting his company was among the first payloads to fly on Electron, given Rocket Lab and Planet had shared an ethos of "dreaming big".
"The Electron will be a game changer in a traditionally difficult launch market. We are excited to quite literally be riding the leading edge with Rocket Lab."
Spire chief executive Peter Platzer said his company was proud to be on board the inaugural deployment attempt.
"The ability to iterate quickly and execute on an incredibly high level is core to the success of both Rocket Lab and Spire. 'Still Testing' is a culmination of that work into a single event," he said.
