How do employers securely transmit payroll files to SSA's PIE system (formats, APIs, SFTP)?
Executive summary
Employers and payroll providers deliver wage data to SSA through a handful of secure channels: established Business Services Online (BSO) upload methods (W-2 Online and Wage File Upload), pilot web services, and approved file-transfer mechanisms such as SSA’s File Transfer Management/System or other secure transfer tools identified in formal information-exchange agreements (PIE and related state agreements) [1] [2]. The PIE program itself establishes automated, recurring exchanges between SSA and payroll data providers under statutory authority; the agency has published proposed rules, POMS guidance, and privacy PIAs that describe formats, protective controls, and that the EWR suite accepts SSA-published file formats and SSL- or agency-approved secure-transfer methods [3] [4] [1] [5].
1. How SSA expects payroll data to be formatted before transmission
Large employers and third‑party submitters use SSA’s published wage-file formats—typically the electronic W‑2 layout or the Wage File Upload schema—when sending bulk payroll data; SSA’s Electronic Wage Reporting (EWR) suite explicitly accepts “large files, using a published SSA format” for Wage File Upload and W‑2 reporting, and employers must use Form W‑2 conventions when reporting wages electronically [1] [6]. The Electronic W‑2 Filing User Handbook recommends compressing large submissions (zip) to speed transmission and references specific accepted compression tools and that files should conform to SSA’s published structural rules [6]. The PIE program also relies on data mappings and reconciliation guidance captured in POMS and PIE-specific agreements to align payroll-provider schemas with SSA’s Wage and Employment Information Repository [4] [1].
2. APIs and web-service options — what exists and what’s pilot vs. production
SSA’s EWR suite includes a Web Service pilot that lets authorized submitters exchange wage records via an API-style service; the agency characterizes this as a pilot under EWR alongside Wage File Upload and W‑2 Online, indicating a move toward machine-to-machine exchanges for automated reporting [1]. Separately, the Payroll Information Exchange model contemplates automated, recurring exchanges with payroll data providers (PDPs) under Section 824 of the Bipartisan Budget Act; SSA’s proposed rule and POMS entries discuss using these information exchanges to obtain electronic payroll data from PDPs, but detailed public API specifications and production-level PIE endpoints are described in program agreements rather than the high‑level federal register notice [3] [7] [4].
3. Secure transfer channels: SSL, FTMS, SFTP and agency‑approved systems
Historically SSA’s Business Services Online communications have used Secure Sockets Layer (SSL) with 128‑bit encryption for web-based submissions, and the EWR suite collects submissions via secure web applications [6] [1]. PIEs and formal information-exchange agreements stipulate that transmissions occur by “method of transfer” listed in the agreement—examples include SSA’s File Transfer Management System (FTMS) or other secure mechanisms approved by SSA [2]. While SFTP is a common secure-transfer tool in enterprise payroll workflows, the public materials provided point to SSA-approved transfer mechanisms in agreements rather than listing SFTP explicitly; FOIA documents and SSA contracts with commercial PDPs (e.g., Equifax) contain the implementation-level security and transfer requirements but are not fully reproduced in the public rulemaking [2] [8].
4. Privacy, accuracy and the political context that shapes technical choices
SSA frames PIE as a data-driven way to reduce improper payments and reporting burdens, keeping payroll data in a Wage and Employment Information Repository under privacy controls described in SSA FAQs and PIAs [7] [5] [1]. Advocacy groups and FOIA disclosures have raised accuracy and privacy concerns about specific vendor exchanges—NYLAG’s FOIA coverage of the Equifax arrangement highlighted accuracy-studies, contractual standards, and security addenda while questioning downstream correction processes—showing how technical transfer choices are inseparable from trust and oversight debates [8] [9]. SSA’s federal register notice and POMS guidance acknowledge reliance on vendor databases like The Work Number and note limits to representativeness and necessary reconciliation procedures [3] [9].
5. Bottom line and limits of public documentation
In practice, employers and payroll vendors transmit payroll to SSA via SSA’s established EWR channels—W‑2 Online, Wage File Upload (published SSA formats, zipped as needed), and the EWR web-service pilot—while PIE arrangements rely on recurring automated exchanges through SSA‑approved secure transfer mechanisms such as FTMS or other methods specified in legal information‑exchange agreements; encryption and formal contractual privacy/security provisions are standard parts of those agreements [1] [6] [2]. Public sources describe formats and approved mechanisms at a program level, but they do not publish full, production API specifications or every approved transfer protocol for PIE—those implementation details appear in agency agreements and vendor contracts disclosed through FOIA or supplier documentation [2] [8].