Global Short-Term Assignments: Compliance Considerations and Best Practices for HR Leaders

In Part One of this series, we explored the rising popularity of short-term international assignments (STAs) and their strategic advantages—from cost savings and rapid deployment to leadership development and global market testing. But while STAs offer agility and efficiency, they also come with unique risks that HR and mobility leaders must carefully manage. In this follow-up post, we dive into the compliance challenges and operational best practices associated with short-term assignments, We’ll also share actionable strategies to help you build a structured, risk-aware STA program that delivers value without unintended consequences.

Challenges and Compliance Considerations for Short-Term Assignments

Despite their shorter duration, STAs are not without risks. HR and global mobility managers should be particularly mindful of the following:

Tax and Social Security Complexity

• Income Tax Exposure

Most countries have a 183-day threshold after which a person may become liable for host-country income tax, even if they remain on home payroll. However, tax liability can be triggered earlier in some cases.

• Tax Equalization Pitfalls

If not managed properly, employees could face unexpected tax bills, or companies may overpay for unnecessary gross-ups.

• Social Security Contributions

Some countries require contributions after a short period. Where totalization agreements do not exist, employees and employers may be double-taxed.

Permanent Establishment Risk

• If an assignee engages in contract negotiation, revenue generation, or strategic decision-making in the host country, they could inadvertently trigger corporate tax liability for the employer.
• This is a growing area of scrutiny among tax authorities.

Immigration and Work Authorization

• Many companies mistakenly send short-term assignees on business visitor visas, which often do not permit paid work or long stays.
• Consequences of noncompliance include fines, entry bans, reputational damage, and delay in project delivery.

Labor Law Protections

• Employees on short-term assignments may be covered by local labor protections, including minimum wage, working time, and termination notice requirements—even if paid from their home country.

Tracking and Oversight

• Without centralized visibility, employees may stay beyond permitted visa or tax thresholds, fail to file required documentation, or create downstream compliance or reputational issues.

Best Practices for Managing Short-Term Assignments

A well-managed short-term assignment program combines flexibility with structure. Here’s how to get it right:

1. Develop a Dedicated STA Policy

Do not lump STAs into your long-term or business travel policies. A clear, consistent STA policy ensures:

• Equitable treatment of employees
• Predictable costs
• Streamlined approvals and communication

2. Build Pre-Assignment Checkpoints

Use pre-assignment assessments to evaluate:

• Immigration requirements
• Tax liability and PE risk
• Social security obligations
• Health and safety needs

3. Track Everything

Use a mobility platform to track:

• Start/end dates
• Time in host country
• Visa/work permit status
• Tax thresholds
• Program costs

This visibility is critical to avoiding compliance issues.

4. Assess Tax and Immigration Risk Pre-Assignment

Build in a formal pre-assignment review process to:

• Model likely tax liability
• Assess PE and payroll risk
• Ensure appropriate visa category
• Flag social security requirements

5. Educate Business Leaders

Ensure stakeholders understand:

• When an STA is appropriate
• What approvals are needed
• The difference between a business trip and an STA

This avoids policy circumvention and rogue deployments.

6. Engage Trusted Vendors

Partner with tax, immigration, and relocation experts who:

• Understand STA-specific risks
• Offer scalable solutions
• Can support employees in-country as needed

7. Prepare the Employee

Even without a full relocation, STAs constitute a significant life event. Support the assignee with:

• Pre-departure checklists
• Cultural training (even brief)
• 24/7 contact for support while abroad
• Regularly scheduled home leave trips

8. Plan for Post-Assignment Reintegration

Clarify:

• Role upon return
• Knowledge transfer plan
• Career development next steps

This maintains engagement and prevents attrition.

STAs vs. Other Mobility Options: How Do They Compare?

Final Thoughts: STAs as a Strategic Mobility Tool

Short-term international assignments are more than a workaround—they are a strategic tool for organizations that need to move talent efficiently, develop future leaders, and contain costs. When managed carefully, STAs can deliver meaningful business value while reducing the risks and burdens often associated with long-term assignments.

However, as with any global move, compliance remains critical. Immigration, tax, and labor law exposure must be actively managed, and employees should receive consistent, structured support throughout the assignment lifecycle.

At TRC Global Mobility, we help organizations design and manage global mobility programs—including short-term assignment strategies—that align with their business goals, support their employees, and minimize risk. As an employee-owned company, we have a vested interest in delivering responsive, high-touch service and successful outcomes.

Is your company making the most of short-term international assignments?
Let’s discuss how TRC can help you create a flexible, compliant STA program that delivers results. > Contact Us