An IT contractor placed through a recruitment agency gathers the payslips, writes a clean letter, submits everything, and still draws a rejection. The cause is almost always identical: the ACS skills assessment reference letter arrived on the agency's letterhead instead of the host company's. ACS reads that as the wrong source, and for agency-placed applicants it is the single fastest way to fail. This guide covers who must sign your letter, every field it has to carry, and what to do when the host company has closed or simply refuses. For a full picture of where the reference letter fits in the broader process, the ACS Skills Assessment Guide 2026 is worth reading alongside this one.
Why Agency Placements Follow a Different Reference Letter Rule
The rule is not ambiguous. In its recruitment-agency guidance, ACS states the reference must come from "the employer they contracted you into, known as a host company," and that your supervisor or manager at that host confirms your roles, tasks, and key achievements. The agency that found the role, signed your contract, and ran payroll is not the author ACS is asking for.
Why? ACS wants a signatory who "witnessed or supervised your work and key deliverables." An agency account manager processed your placement; they never sat in your stand-ups or reviewed a line of your code. That single distinction drives the entire requirement.
Your agency payslips are not wasted. ACS accepts payment evidence "issued by the recruitment agency" even while it insists the letter itself come from the host. Keep those payslips; they corroborate your dates and salary. Just don't expect them to stand in for the employer letter.
Map Every Host Company Before You Ask for a Letter
Before you email anyone, list every host company where you performed skilled ICT work under your agency contracts. ACS assesses experience per employer: its experience-evidence guidance requires a host-company letter for each relevant employer, with every employment period logged separately in the application portal.
That carries a sharp consequence for anyone who rotated. If one agency contract placed you at three client sites across four years, you need three letters, one from a supervisor at each host. A single consolidated agency letter summarising all of it does not satisfy ACS, regardless of how tidy it looks.
Long placements are where applicants assume they can cut a corner. Five unbroken years embedded at one host under a rolling agency arrangement still means the letter comes from that host's supervisor, never the agency.
Step 1: Find the Supervisor Who Can Actually Sign
The qualifying signatory is narrow. It must be someone who witnessed or supervised your work and key deliverables. That rules out the HR coordinator who onboarded you, the agency contract administrator who managed your timesheets, and any representative who never observed what you built. Seniority alone is not the test. Direct oversight of your work is.
Approach that person with the heavy lifting already done. A busy engineering manager is unlikely to prioritize an unfamiliar documentation request without guidance. Send a short brief naming what ACS needs, supply your exact employment dates, and offer a draft they can edit rather than a blank request. Explain in one line why it must be on their company's letterhead and not the agency's, because that is the question they will ask first.
Step 2: Brief Your Supervisor on Every Mandatory Field
ACS lists thirteen mandatory fields, and a reference that omits any of them "will not be assessed." Give your supervisor the full set so nothing gets missed:
Company letterhead showing the host employer's name and address
Company website URL
Your full legal name
The date the letter is written
Employment start and end dates in DD/MM/YYYY format
Employment status (permanent full-time, part-time, or contractor)
Minimum weekly hours worked
Annual salary before tax and benefits
Work location (in Australia or outside Australia)
Your position or role title
Bullet-point duties you actually performed
The signatory's authorised signature
The signatory's full name, position title, phone number, and work email
Annual salary before tax is the field applicants miss most, largely because most competitor checklists leave it off entirely. Its absence alone can send the letter to non-assessment, so confirm it is there.
The duties section is where the letter is won or lost. Map each duty to your nominated ANZSCO unit group, but write it in real language about real projects. ACS is explicit: "Duties copied directly from Occupations and ANZSCO codes or from another reference will not be accepted." Lifting the unit-group description verbatim is a named rejection trigger, not a stylistic slip. Describe what you designed, shipped, and owned, then check that it reflects the unit group rather than reciting it.
If you held more than one role at the same host, ACS specifies the format: a table with columns for Position Title, Start Date, End Date, and Location, with a separate duty list under each role. Two positions should not be blurred into one paragraph.
Step 3: Check the Draft Against ACS Rules Before You Submit
Run four checks on the returned draft, because most agency-applicant rejections come from the same handful of misses. Start with the letterhead and the named employer: both must be the host company, not the agency. Next, verify the signatory is a witness-level supervisor with full contact details. Confirm all thirteen fields are present, salary included. Finally, read the duties to ensure they are specific to your work and not copied from ANZSCO.
The most common defect in an agency worker's ACS skills assessment reference letter is a draft that credits the agency as "employer." A well-meaning supervisor may write "employed via [Agency] on assignment to us." That framing inverts the rule. For assessment purposes, the letter must present the host company as the employer of record, with the agency mentioned only, if at all, as the contracting mechanism. If the draft attributes employment to the agency, send it back and ask for a plain statement that you worked at and were supervised by the host. For a broader view of what sinks applications, the ACS rejection-reasons self-audit guide is worth a pass.
Direct Employment vs Agency Placement: What Changes in the Letter
Most guides treat every reference the same. The two situations diverge on specific points, and locating yours takes ten seconds:
Variable | Direct employment | Agency placement |
|---|---|---|
Letter author | Your employer's supervisor | Host company supervisor, never the agency |
Letterhead | Your employer's | Host company's |
Dates source | Employer records | Host records, corroborated by agency payslips |
Duty framing | Mapped to nominated ANZSCO, in your words | Same, framed around your host-project work |
Signatory qualifier | Manager who supervised you | Someone who witnessed the work, not HR or agency admin |
Payment evidence | Employer payslips | Agency payslips accepted |
The long-term single-host case still shifts one thing: nothing about the letterhead or author relaxes just because the placement was stable. The host writes it, every time.
When the Host Company Will Not Write Your Letter
A statutory declaration cannot travel alone. ACS requires it to be accompanied by "a letter or official email from the company explaining why an employment reference letter cannot be provided." Submit the declaration without that companion document, and it is treated as insufficient. Your first move when a host declines is to secure a brief written or emailed refusal from the company, not to reach for a stat dec.
The declaration itself has strict conditions. It must be sworn or witnessed, carrying the "Sworn Before, Signed Before or Witnessed Before" language, and the declarant must be a supervisory or managerial colleague who directly observed your duties. ACS rejects declarations from junior colleagues, self-written declarations (except for the genuinely self-employed), and any that copy duties from ANZSCO codes or omit overlapping employment dates.
When the host is defunct or your supervisor has vanished with no witness-level replacement, build corroboration from what you still hold: agency payslips, tax records, and superannuation statements that establish the dates and salary. These support a case; they rarely carry it alone. A statutory declaration backed by that paper trail, plus a company or director's confirmation, is the strongest fallback available. The ACS eligibility documents guide breaks down what each supplementary record proves.
What Agency Workers Ask About the ACS Skills Assessment Reference Letter
Can my recruitment agency write the ACS reference letter on my behalf?
No. ACS requires the letter to come from the host company where you performed the work, signed by a supervisor who witnessed it. The agency can supply payslips as payment evidence, but it cannot author the reference.
Does the letter need host company or recruitment agency letterhead?
Host company letterhead. A reference on agency letterhead is the leading rejection trigger for agency-placed applicants. The letterhead must name the host employer and its address, because ACS reads the letterhead as a statement of who is attesting to your work.
What if I worked at multiple host companies through the same recruitment agency?
One letter per host company where skilled work occurred, each signed by a supervisor at that host. A single agency letter covering all placements is not acceptable, and each employment period is recorded separately in the portal.
What should I do if my host company supervisor refuses to write the reference letter?
Ask another supervisory or managerial colleague who directly observed your work to provide a sworn statutory declaration, and pair it with a letter or official email from the company explaining why a standard reference cannot be issued. The declaration alone will not pass.
How far back can my employment reference letters go for an ACS assessment?
ACS publishes no fixed lookback cutoff on its InfoHub. It counts employment after you turn 18 regardless of whether it pre-dates or post-dates your degree, though experience gained after your qualification completes typically carries more weight in a points-based assessment. ACS requires at least 20 hours per week and excludes unpaid leave, unpaid internships, and volunteer work; each qualifying period must be recorded separately.
Does the signatory need to include direct contact details?
Yes. The signatory's full name, position title, phone number, and work email are mandatory fields. ACS may contact them to verify the reference, so a shared inbox or missing number can hold up your assessment.
Before you submit, confirm every supporting document is actually in place. Run your reference against the ACS document checklist to make sure the letter is backed by everything else ACS expects, and if you are still choosing a route, the pathways overview shows where the reference letter fits in the overall application.