Eligibility check coverage

On almost every item in the Medicare Benefits Schedule (MBS), RebateRight gives a clear eligible or not eligible. On a small set (167 items, 2.8% of the MBS), we sometimes return cannot determine instead: never a wrong answer, just an honest “we can’t confirm this one.” Whether it affects you depends on what you bill.

When you’ll see cannot determine

You’ll only see cannot determine when all four of these are true at the same time:

• the patient is treated out of hospital
• the item is one of the 167 listed below
• the patient’s Medicare details are valid
• every other RebateRight check passes, such as the referral and the patient’s age

If any one of these is not true, you get a clear eligible or not eligible instead, with the reason. So even on these 167 items, RebateRight still catches what it can: a wrong Medicare detail or a failed rule is flagged before the claim goes in.

When all four are true, cannot determine tells you the claim has already passed everything RebateRight can check: the patient’s Medicare details matched, and every other check passed. The only thing left is how many times the item has already been claimed. These items have a limit on that, and out of hospital, Services Australia doesn’t share the patient’s claim history. So rather than guess, we show cannot determine.

See if your items are affected

The 167 items are below (as at July 2026), grouped by MBS category. Search by item number or by what the item is, or open a category to browse. Each number links to its descriptor on MBS Online.

Fully supported, with a clear answer on every item:

• Category 4 · Oral and maxillofacial services · 0 items
• Category 7 · Cleft lip and palate services · 0 items
• Category 10 · Child Dental Benefits Schedule · 0 items

Indicative items

Services Australia verifies most MBS items live. For the rest, RebateRight applies the MBS rules itself and still gives you a clear eligible or not eligible, an indicative result. It’s a strong answer from our own checks, not a live Services Australia confirmation, and it’s marked so you always know which kind you have.

The 167 items above are the indicative items that also have a limit on how often they can be claimed. That’s the one check we can’t confirm out of hospital, so they’re the only ones that can return cannot determine.

Indicative items are named in section 7 of our Licence Agreement.

Reciprocal Medicare cardholders

Patients covered by Australia’s Reciprocal Health Care Agreements (RHCAs) carry a reciprocal Medicare card. They’re entitled to medically necessary care while in Australia, and they’re subject to the same MBS item rules as a standard cardholder, including claim frequency limits. Cover terms vary by country: see Reciprocal Health Care Agreements on the Services Australia site, or MBS note GN.3.9.

Services Australia doesn’t support online eligibility checks for reciprocal cardholders. Where it can, RebateRight runs its own validations, such as the patient’s age, and returns one of two results:

• not eligible: the patient fails a check RebateRight can run.
• cannot determine: RebateRight couldn’t verify the patient’s claim history, so the frequency-of-service limit can’t be confirmed. As with any cannot determine, it’s an honest “we can’t confirm this one,” not a rejection.

For developers

Pull the set. List GET /MedicareItems and keep items where BenefitType is _85 or _100 and ClaimHistoryLimitation is not empty.

In an eligibility response, cannot determine is IsEligible: null with a MedicareUnverifiedItem reason code. It’s returned only for out-of-hospital requests where every RebateRight check passes. A failed check returns IsEligible: false with the reason. An in-hospital request returns the live result.

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GET /CalculateRebate -> Rebates[]
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{
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  "ItemNumber": "701",
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  "IsEligible": null,
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  "ReasonCode": "RREligible|MedicareUnverifiedItem",
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  "Reason": "[RebateRight] All RebateRight eligibility checks have passed ... [RebateRight] Services Australia doesn't verify this item online ... we can't confirm its frequency-of-service limit.",
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  "Benefit": "0"
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}