With GitHub Copilot moving to usage-based billing (GitHub AI Credits) on June 1, 2026, choosing the right AI model for each task becomes a real cost concern. The core strategy is a 'model ladder': use large frontier models (Claude Opus 4.7, 15x multiplier) only for planning, architecture, and complex reasoning; use mid-tier models (Claude Sonnet, GPT-5.2, 1x) for daily implementation work; and use small models (Claude Haiku, GPT-5.4 mini, 0.33x) for summaries, commit messages, and boilerplate. A practical 4-step workflow is outlined: plan with a large model, implement with mid-tier, clean up with small, and escalate only when stuck. Prompt hygiene also matters under token-based billing — keep prompts focused, avoid pasting unnecessary context, and stop bad runs early. Teams should establish model-selection guidelines and review which models are enabled before the billing change takes effect.
