Introduction
What is Milena?
Milena is a payroll management software developed by Seresco, designed to automate and simplify all processes related to employment management and payroll calculation.
The integration between Factorial and Milena connects your HR system with your payroll system, automating the transfer of information between both platforms.
With this integration, you will be able to:
- Synchronize employee data
- Reduce manual data entry errors
- Save time on administrative and payroll processes
Process and Functionalities
The integration works in both directions, depending on the configuration:
Architecture
The integration has been developed by our Technology Partner Illusion Studio.
It is based on:
- Consumption of the Factorial API.
- File generation via SFTP for Milena.
- Manual validation in Milena before creating or updating records.
In the Milena interface, an HR validation form is displayed so the HR team can review the information before confirming it.
Synchronized data
From Factorial to Milena
- Employee creation (personal data only, no contractual data)
- Employee terminations (termination date and reason)
- Employee updates (personal data only)
- Payroll supplements (file generated and sent by email, not automatically imported)
From Milena to Factorial
- Payroll documents (PDF)
- Withholding certificates (daily overnight synchronization)
Synchronized fields
| Synchronized | Not synchronized |
|---|---|
| Personal data | Contractual data |
| Hires and terminations | Salaries |
| Termination reasons | Absences |
| Payroll documents | Time tracking |
| Tax certificates | Accounting |
Data that is synchronized
From Factorial → Milena (Hires, Updates, and Terminations)
| Category | Factorial field | Milena field | Notes |
|---|---|---|---|
| Identification | First name | Name | Free text |
| Identification | Last name(s) | Last name 1 / Last name 2 | Automatically split |
| Identification | DNI / ID | Document | Must exist beforehand in Milena |
| Social Security | Social Security Number | SSN | 14 digits, no separators |
| Organization | Legal entity | Company | Code must match |
| Organization | Work center | Center | Mandatory |
| Organization | Department | Department | Must exist in Milena |
| Organization | Cost center | Cost center | One per employee only |
| Contact | Primary | ||
| Contact | Phone number | Phone | Personal prioritized |
| Address | Full address | Street | Single field |
| Employment status | Hire date | Start date | |
| Employment status | Termination date | End date | |
| Employment status | Termination reason | Termination reason | Synced codes |
From Milena → Factorial (Documents)
| Document type | Source | Frequency | Destination in Factorial |
|---|---|---|---|
| Payslip | Milena | Monthly | Employee documents (PDF) |
| Withholding certificate | Milena | Daily (overnight job) | Employee documents |
Payroll supplements
| Source | Format | Method |
|---|---|---|
| Factorial | Seresco file format | Email delivery (no automatic import) |
Fields that are not synchronized
Contractual information (not sent from Factorial to Milena)
| Category | Field | Reason |
|---|---|---|
| Contract | Contract type | Integration syncs employee data only |
| Contract | Contract start date | Out of scope |
| Contract | Contract end date | Out of scope |
| Contract | Working hours / % | Managed exclusively in Milena |
| Contract | Base salary | Salary data not synchronized |
| Contract | Professional category | Managed directly in Milena |
| Contract | Collective agreement | Not mapped |
| Contract | Contribution group | Not synchronized |
Financial and accounting data
| Category | Field | Reason |
|---|---|---|
| Accounting | Accounting accounts | Out of connector scope |
| Accounting | Automatic journal entries | Not generated from Factorial |
| Accounting | Analytical allocation | Not supported |
| Accounting | Payroll history | Only new documents are synchronized |
Time and absences
| Category | Field | Reason |
|---|---|---|
| Time | Vacations | Not integrated with payroll |
| Time | Sick leave | Not synchronized |
| Time | Absences | Not synchronized |
| Time | Overtime | Not synchronized |
| Time | Shifts | Not synchronized |
| Time | Time tracking | Not synchronized |
Other unsupported data
| Category | Field | Reason |
|---|---|---|
| Customization | Custom fields | Not mappable in Milena |
| Organization | Manager | No matching field |
| Organization | Org chart | Not synchronized |
| Organization | Multiple cost centers | Only one allowed |
| Documents | Non-payroll attachments | Only payslips and certificates |
How to set up the integration
Step 1: Enable the integration in Factorial
- Go to Settings → Integrations.
- Select Milena and click Connect.
- Your Factorial Account Manager will contact you to:
- Share the documentation.
- Coordinate onboarding with Illusion Studio.
Step 2: Field mapping configuration
You will receive a configuration file to define the field mapping between both systems together with your consultants (Seresco and Factorial).
Key fields to review:
- Legal entity (mandatory)
- Work center (must match Milena exactly)
- Termination reasons (verify codes)
Save the configuration once validated.
With your IT team, you must generate a subdomain (URL) to connect to the server and share it with Illusion Studio.
Step 3: Validation
- Create or update a test employee.
- Verify that the data is correctly reflected in Milena.
If errors occur, review the field mapping.
Limitations and Technical Considerations
Fields and formats
- Last names: Factorial uses a single field; Milena splits them automatically.
- Social Security Number: Must contain 14 consecutive digits, with no spaces or hyphens.
- Address: Sent entirely in the “Street” field.
- Phone numbers: Personal phone is prioritized; if unavailable, the work phone is used.
-
Email: A single primary email address is recommended.
Synchronization rules
- The trial period may be overwritten depending on the professional category in Milena.
- Some fields apply only to part-time contracts.
- Only one cost center per employee is supported.
- Departments must be previously configured in Milena.
-
Supplements must follow the Seresco format.
Geographic scope
Available features depend on the country (Chile, Colombia, Puerto Rico, Germany, and the United States).
Dropdown lists must be aligned in both systems.
Frequently Asked Questions (FAQs)
-
Who is Illusion Studio?
Illusion Studio is the Technology Partner that developed and maintains the Factorial–Milena integration.
-
Does the integration have a cost?
Yes. There is a recurring monthly fee for maintenance, updates, and support.Please contact your Account Manager for more details.
-
Is synchronization real-time?
No. The frequency is defined during the initial setup with the Partner.
-
What happens if a field does not exist in Milena?
That data will not be synchronized and must be managed manually or created beforehand in Milena.
-
Can I configure different variables by country?
Yes. Lists and variables are configured per country.
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Why does the address appear in a single field?
Because Factorial sends the full address in one single field.
-
What should I do if synchronization fails?
Review the field mapping.
Validate entity and center codes.
Contact support if the issue persists.
-
Where can I report issues?
- Send an email to:
soporte@illusionstudio.es - Always include:
- Steps to reproduce the issue.
- Evidence or screenshots.
- Send an email to: