When SIN 531 fits
SIN 531 quick facts
A compact view of the official SIN record from the user's Refresh 32 MAS offerings workbook.
What SIN 531 covers
531 Includes all services relating to employee relocation, such as home sale assistance, property management, and household goods shipment coordination.
The official record maps this SIN to NAICS 531210 and PSC V301. Those codes are not the whole strategy, but they help explain how the offering is categorized for buyers and reviewers.
How to prepare the offer story
For service-oriented SINs, keep the service description, labor categories, pricing support, and past-performance examples aligned. A reviewer should be able to see what work is being sold, who performs it, and why the rate story is defensible.
If the SIN is being added through eMod, write down what changes operationally: new scope, new pricing, new files, catalog impact, and who owns maintenance after approval.
Buyer and SEO language to keep straight
Use the SIN number, title, category, and subcategory together: SIN 531 - Employee Relocation Solution - Travel - Employee Relocation. That combination helps a buyer understand the lane quickly and helps the page avoid becoming a vague keyword page.
When writing capability language, explain the actual deliverables and evidence. Do not make the SIN carry the whole message by itself.
What this looks like in practice
Real-world checkHow to test SIN 531 before building files
Start with the official title and description: Employee Relocation Solution sits under Travel > Employee Relocation. Then compare your actual commercial offering to that scope, not only to the NAICS code.
If the fit still looks strong, build the proof stack: offering description, pricing support, past performance or product support, and any SIN-specific files the current GSA instructions require.
- Confirm scope language.
- Check NAICS and PSC signals.
- Match the pricing file to the offering type.
- Keep the support package reviewer-friendly.
Frequently asked questions
Is SIN 531 part of TDR?
The Refresh 32 workbook marks TDR as Y for this SIN. GSA states that TDR became mandatory across MAS SINs with Refresh 31, so contractors should still verify current contract reporting instructions in official GSA sources.
Can order-level materials be used with SIN 531?
The workbook marks OLM as Y. OLM treatment should always be verified against the current MAS solicitation, mass modifications, and contract-specific instructions.
Should I pick a SIN only because the NAICS matches?
No. NAICS helps, but SIN selection should be based on the actual offering, official SIN description, category/subcategory, pricing files, and buyer acquisition path.