Workday vs Workday Legacy — Why Unified.to Supports Both
July 25, 2025
Workday provides two main API integration formats:
- Workday REST API — their latest modern API, but still under active development.
- Workday SOAP API (often referred to as Legacy) — the older but mature API that still covers some critical endpoints not yet available in REST.
To give you maximum flexibility and to ensure you can access all the data and actions you need, Unified.to supports both APIs.
Why You Might Need Both
While Workday is steadily improving their REST API, there are still a few important gaps. Here's why using both makes sense today:
- Application Creation — Workday's REST API does not currently support creating job applications. This is only available through the Legacy SOAP API.
- Candidate Lists — Retrieving a full list of candidates is not yet supported in REST but is fully available through the Legacy SOAP API.
- Create Job — Similar to applications, creating jobs still relies on the Legacy API.
- Attachments — The REST API does support listing and downloading attachments — which the Legacy SOAP API does not.
- Future Coverage — Workday continues to expand REST API features. As new endpoints become available, Unified.to will adopt them immediately so you always have the best option.
| WorkDay REST | WorkDay Legacy | |
|---|---|---|
| ATS Activity | List | |
| ATS Application | List, Get, Create, Update | |
| ATS Candidate | Create, Get | List, Get, Create, Update |
| ATS Document | List, Get, Create, Download | |
| ATS Interview | List, Get | List, Get, Create, Update |
| ATS Job | List, Get | List, Get, Create, Update |
| ATS Scorecard | List, Get | List, Get, Create, Update |
| HR Employee | List, Get | List, Get, Create, Update |
| HR Group | List, Get | |
| HR Timeoff | List, Get | |
| Accounting Contact | List, Get | |
| Accounting Invoice | List, Get |
Frequently Asked Questions & Answers
Question: Do I have to send XML requests for Workday Legacy?
Answer: No! You always send JSON requests to Unified.to. We handle the conversion to XML behind the scenes for the SOAP API.
Question: Can I use both the REST and Legacy APIs at the same time?
A****nswer: Absolutely. Unified.to lets you mix and match endpoints. For example, you can fetch attachments with REST and create applications with Legacy — all through the same unified model.
Question: Is the Workday Legacy connector going to be deprecated?
A: Not anytime soon. Many Workday customers still rely on SOAP endpoints for critical operations. Unified.to will continue supporting it as long as Workday does.
Question: Is authentication different for Legacy vs REST?
Answer: Yes — Workday REST typically uses OAuth 2.0, while the Legacy SOAP API uses basic authentication (aka WS-Security). Unified.to handles this complexity for you.
Question: Are the data models the same between REST and Legacy?
Answer: Yes — Unified.to normalizes the data, so you get a consistent unified schema, no matter which Workday API is behind the scenes.
Question: Can I switch from Legacy to REST later?
Answer: Yes. As Workday expands REST support, you can migrate endpoints over time. Our team will help you adapt with minimal changes on your side.
Question: Will using both cost more?
Answer: No — there's no extra fee for using both. You only pay for your overall Unified.to usage.
Conclusion
Workday is gradually moving more features to its modern REST API — but some critical workflows still require the mature SOAP-based Legacy API. To ensure you don't lose any capability, Unified.to supports both — giving you the best of both worlds.
Our recommendation: Use the REST API wherever possible for modern features and attachments, and rely on the Legacy API to cover any gaps (like creating jobs or applications). Unified.to handles all the complexity behind the scenes, so you can build faster with no surprises.
Have more questions?
Reach out to our support team — we're here to help you get the best out of both Workday APIs!