Smart Leasing and MillarX — why their quoted figure needs adjusting in the calculator
If you have a quote from Smart Leasing or MillarX and have tried entering the quoted fortnightly or monthly figure directly into this calculator, the effective interest rate will come out higher than expected — often by more than 1%. This reflects a structural difference in how these two providers quote their payment amounts.
How most providers structure their payments
Two separate parties are typically involved in each novated lease’s financing arrangement: the novated lease provider (technically a salary packaging company) and a financier. While one company may be your novated lease provider, the source of finance is usually a separate bank — Westpac, CBA, and similar.
The underlying finance is usually structured with a 2-month deferral (occasionally 1-month). In other words, in a 5-year lease with 60 months duration, this is often structured as a 2-month deferred period where the lease begins but no payment is due to the financier, followed by 58 months of monthly commitment. This deferral is a structural design to account for delays in the starting weeks of the lease, where both remittance and accumulation of funds may lag behind the payment schedule.
Now assume the financier’s monthly payment is $1,000 ex-GST1 for 58 months, or $58,000 total.
Typically, the novated lease provider then collects $58,000 over the entire 130 fortnights — that is, $58,000 ÷ 130 = $446.15 per fortnight ex GST.
What Smart Leasing and MillarX do differently
Both Smart Leasing and MillarX use a structure in which they collect finance payments as though you are paying across the full lease term (60 months in this example), even though the financier is only asking for 58 months. The excess is kept as a buffer for running costs.
Smart Leasing typically withholds 2 months’ worth of payments as a reserve. Using the same $1,000/month example for a 60-month lease:
- The bank expects $1,000 × 58 = $58,000 in total finance payments.
- However, Smart Leasing collects $1,000 × 60 = $60,000 total from the employee.
- The $2,000 difference is not a true finance cost — it is held as a budget reserve.
MillarX typically withholds 1 month. Using an analogous example:
- The bank expects $1,000 × 59 = $59,000 in total finance payments.
- However, MillarX collects $1,000 × 60 = $60,000 total from the employee.
- The $1,000 difference is not a true finance cost — it is held as a budget reserve.
The budget reserve is used to cover any shortfall in the budgeted running costs. Any surplus at the end of the term is refunded to you.
Why this inflates the effective interest rate in the calculator
This calculator models the true cost of the finance arrangement — the vehicle cost, interest, and residual. To do that accurately, it needs the figure that reflects what is actually being paid to the financier, not what is being deducted from your salary.
When you enter the quoted figure from Smart Leasing or MillarX directly, you are entering a number that is slightly higher than the true finance cost — because of the over-collection for the budget reserve. This inflated figure produces a higher effective interest rate than the genuine finance cost would.
The maths is straightforward. For a 5-year lease with Smart Leasing (2 buffer months):
True finance figure = Quoted figure × (58 ÷ 60) = Quoted figure × 96.67%
Your quoted figure is ~3.45% higher than what the calculator needs. On a $600/fortnight quote, the correct figure is around $579.
For a shorter lease the effect is larger, because the buffer months represent a larger share of the term:
| Lease term | Smart Leasing buffer | Payment overstatement |
|---|---|---|
| 5 years (60 months) | 2 months | ~3.45% |
| 4 years (48 months) | 2 months | ~4.26% |
| 3 years (36 months) | 2 months | ~5.88% |
| 2 years (24 months) | 2 months | ~9.09% |
| Lease term | MillarX buffer | Payment overstatement |
|---|---|---|
| 5 years (60 months) | 1 month | ~1.69% |
| 4 years (48 months) | 1 month | ~2.13% |
| 3 years (36 months) | 1 month | ~2.86% |
| 2 years (24 months) | 1 month | ~4.35% |
These percentages represent the overstatement of the payment figure, not the direct difference in effective interest rate — though a payment overstatement of this magnitude does translate to a meaningful inflation of the back-calculated effective rate, typically 1% or more.
The adjustment tool in the calculator
The calculator includes a built-in adjustment tool specifically for these providers. It appears as “Smart / MillarX?” inline with the per-fortnight / per-month toggle on the vehicle finance input field. Clicking it opens a panel where you can:
- Select your provider (Smart Leasing or MillarX)
- Enter your quoted figure (per fortnight or per month — both are supported)
- Read off the adjusted figure to enter into the calculator
The panel shows the scaling factor, the adjusted result, and an explanation of the buffer being applied.
The buffer months used in this tool — 2 for Smart Leasing, 1 for MillarX — reflect the most commonly reported structure. Individual quotes may vary.
Why the calculator total will look lower than your provider’s quote
Once you apply the adjusted figure, you will notice that the calculator’s total cost comes out slightly lower than the total your provider quotes for the same arrangement. This is expected.
Your provider’s quoted total is calculated inclusive of the budget reserve — which overstates the true out-of-pocket cost, because that reserve is refunded to you if unused at term end.
The figure in your provider’s quote represents the cost before any reserve refund. This calculator models the cost net of it.
The difference in total cost between the two figures is approximately:
Buffer months × Monthly equivalent payment
For a Smart Leasing quote of $600/fortnight on a 5-year lease, this is roughly 2 × ($600 × 26 ÷ 12) ≈ $2,600 — money that sits in a reserve and comes back to you if unused, not a genuine cost.
Key takeaway
Smart Leasing and MillarX quote a regular payment derived across the full lease term, but part of that payment funds a running-cost reserve rather than the financier. Entering the quoted figure directly overstates the finance cost and inflates the effective interest rate. Use the “Smart / MillarX?” adjustment tool in the calculator’s finance input to scale the figure correctly before comparing rates or modelling outcomes.
Related reading
- Novated Lease Calculator
- Why effective interest rates look high
- Effective rates on short leases and cheaper cars
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Footnotes
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All figures in this article are expressed ex-GST. In practice, GST is embedded in the amounts that change hands — the financier charges GST on the lease rental, and the employee’s salary deductions include it. We use ex-GST figures throughout because, for most employees, the GST component is largely irrelevant to calculations: employers and novated lease providers claim the input tax credit and pass it on, therefore the employee is usually not responsible for the GST component. ↩