The lowest paid tier, Starter, already includes a commercial license for speech and music, which is the line that matters for monetized content. Move up to Creator or higher when you need more monthly credits, professional voice cloning or higher-quality audio output.
For BuildersOS, we use ElevenLabs on the Starter plan for our voice audio. The free tier does not include commercial rights, so it is not an option for a site that earns money.
The biggest practical gotcha is character cost. A 3,000-word article is roughly 18,000 characters. Plan your monthly budget around expected output, not around the marketing copy on the pricing page.