The Payday Super SGC Calculator estimates the Superannuation Guarantee Charge an Australian employer faces when super contributions for a worker are paid late or not at all. Enter either the contribution shortfall directly or the worker's qualifying earnings, plus how many days late the payment is, and the calculator builds the charge the way the ATO structures it: shortfall, nominal interest, the administration uplift, and the admin fee.
How It Works
If you enter qualifying earnings instead of a shortfall, the shortfall is earnings times the 12% super guarantee rate. Nominal interest then accrues on the shortfall at the rate you enter (the calculator defaults to 11.43%) for the days late:
The charge's sting is the uplift: by default 60% of the shortfall plus interest, reduced when the employer voluntarily discloses (the calculator models disclosure as cutting the uplift by 40%, to an effective 36%). The total SGC is shortfall + interest + uplift + admin fee, and the calculator shows the extra cost over what paying on time would have cost, which is just the shortfall itself.
Parameters
| Input | Required | Meaning | |---|---|---| | Shortfall amount | Either | The unpaid contribution amount | | Qualifying earnings | Either | Ordinary time earnings the SG was owed on (shortfall = 12% of this) | | Interest rate | No | Nominal interest rate; defaults to 11.43% | | Days late | Yes | Days between the due date and payment | | Admin fee | No | Per-employee administration component | | Uplift % | No | Administration uplift; defaults to 60% | | Voluntary disclosure | No | Models the reduced uplift for employers who come forward |
Worked example
An employer owes a 20 admin fee and no voluntary disclosure. Interest is 5,000 x 11.43% x 90/365 = 3,084.55. Total SGC: 5,000 + 140.92 + 3,084.55 + 20 = **3,245.47 more than paying on time. With voluntary disclosure the uplift falls to 36%, 7,011.65, so coming forward saves about $1,234 in this scenario even before any ATO discretion.
Why late super is so expensive
Three features compound. The shortfall is calculated on the broader ordinary-time-earnings base, which can exceed the base the employer used. Interest runs from the start of the quarter, not the due date, in the real system, so even a few days' lateness carries a full quarter's interest start point. And unlike on-time contributions, the SGC is not tax-deductible, while the uplift historically operated as a penalty for a system in which employees had little visibility. With Single Touch Payroll and fund reporting, underpayments surface quickly; the calculator's disclosure toggle exists because the ATO's published approach rewards self-reporting.
Payday super context
Australia's payday super reforms move the obligation toward paying super on payday itself rather than quarterly, which shrinks the window in which a shortfall can hide and makes day counts like the one in this calculator a routine payroll control rather than a quarterly surprise. Employers should treat the days-late input as a number their payroll system reports automatically; if it is ever non-zero, the SGC statement process, not a quiet catch-up payment into the fund, is the compliant route, because paying the fund directly does not extinguish the charge.
Limitations
This is a model of the charge's structure using the inputs and defaults you see, not an ATO assessment. The real SGC includes the shortfall calculated on the salary-or-wages base in some components, interest from the quarter's first day, per-employee per-quarter admin fees, and offsets for late payments actually made. Voluntary-disclosure outcomes are discretionary. Employers with an actual shortfall should use the ATO's SGC statement and seek payroll-tax advice promptly.
Worked example 2: starting from earnings
An employer who missed super on 3,600 before anything else is added. Paid 30 days late at the default 11.43% with a 33.82, the 60% uplift on the shortfall plus interest is 5,834.11 against $3,600 on time. The extra cost of one month's delay approaches two-thirds of the original obligation, which is why payroll controls treat super as a pay-day item rather than a quarterly cleanup.
What payroll should do differently
Reconcile the super clearing-house report against the payroll register every pay run, not at quarter end; a mismatch caught in the same week is a correction, while the same mismatch caught by an ATO review is an SGC statement with interest counted from the quarter's start. Keep the days-late figure visible on the payroll dashboard. The moment it is non-zero, the cheapest action is immediate voluntary engagement with the process, as the worked examples show: disclosure discounts the single largest component of the charge.
Frequently Asked Questions
Can I just pay the fund late and skip the SGC?
No. A late payment to the fund does not cancel the charge; the SGC statement process is how late super is regularized, and amounts paid can be offset within that process. Quiet catch-ups leave the liability alive.
Why is the uplift so large?
The uplift (the Part 7 penalty regime in the real system) exists because employees historically could not see underpayments for years. The modeled 60% default reflects how severely the charge is designed to bite compared with the modest interest component.
Is the SGC tax-deductible?
No, and that is a major part of its cost. On-time contributions are deductible; the charge paid late is not, so the after-tax cost of lateness is higher than the headline figure suggests.