Why
A large single commitment purchase creates a cliff-edge expiration — when it expires, costs jump 30–60% overnight. Laddering (buying smaller amounts at staggered intervals) smooths the portfolio, allows gradual adjustment as usage patterns change, and reduces the risk of over-commitment.
What
Design a laddered purchase strategy that staggers commitment purchases across months to avoid cliff-edge expirations and enable continuous adjustment.
How
Assess Current Portfolio
Map all active commitments by expiry date. Identify clusters where multiple commitments expire simultaneously (cliff edges).
Design the Laddering Schedule
Principle: instead of buying 12 months of coverage at once, buy 1/12th every month (for 1-year terms) or 1/36th every month (for 3-year terms).
| Month | Purchase Amount | Covers | Expiry |
|---|---|---|---|
| Jan | $5K/month equiv | Steady-state | Jan next year |
| Feb | $5K/month equiv | Steady-state | Feb next year |
| … | … | … | … |
Start with the most stable workloads (>6 months of consistent usage). Leave variable workloads on-demand or use Savings Plans (AWS) / Flexible CUDs (GCP) for partial coverage.
Implement Purchase Calendar
Create a monthly commitment review: check utilisation of existing commitments, identify new steady-state workloads eligible for coverage, and execute the next ladder purchase. Track in a spreadsheet or commitment management tool.
Deliverable Checklist
- Current portfolio mapped by expiry date
- Cliff-edge expirations identified
- Laddering schedule designed
- Monthly purchase calendar established
- Utilisation review cadence set (monthly)