> For the complete documentation index, see [llms.txt](https://flapjax.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://flapjax.gitbook.io/docs/hosting/cost-optimisation/images-and-media.md).

# Reserved RDS Instances

Reserved Instances (RIs) allow major cost reductions on Aurora/RDS by committing to 1- or 3-year terms.

### Why Reserved Instances Matter

#### No Upfront

* No initial payment
* 1-year term
* \~30–40% discount

#### Partial Upfront

* Some upfront cost
* 1-year or 3-year term
* \~55–60% discount

#### All Upfront

* Full payment upfront
* \~63–69% savings

### Supported Engines

* Aurora
* MySQL / MariaDB
* PostgreSQL
* Oracle BYOL

### How AWS Applies RI Discounts

* AWS applies RI pricing to matching instance usage.
* Extra usage is billed On-Demand.

### When to Use RIs

* Always-on production databases
* Predictable workloads

### Summary

Reserved Instances provide the most impactful cost savings for long‑lived Flapjax database workloads.