Cheapest 300GB Mobile Plans on Optus
The cheapest 300GB mobile plan on the Optus network is 4G 350GB Asia Plan by circles-life at $10.80/mo.
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Forward your bill7 Plans — sorted by price
Showing plans with 300–450GB data on the Optus network. Postpaid and prepaid only.
Prices validated: 25 June 2026
| Carrier | Plan | Data | Type | 5G | $/mo | Actions | |
|---|---|---|---|---|---|---|---|
 | 4G 350GB Asia Plan | 350GB | Postpaid | No | $10.80 | Switch — $25 | |
| 5G 300GB Asia Plan | 300GB | Postpaid | Yes | $12.88 | Switch — $25 | |
| Circles Plus | 300GB | Postpaid | Yes | $18.00 | Switch — $25 | |
| Circles Plus | 300GB | Postpaid | Yes | $18.00 | Switch — $25 | |
| Circles Plus | 300GB | Postpaid | Yes | $18.00 | Switch — $25 | |
 | 365 Days Plan $179 360GB | 360GB | Prepaid | Yes | $24.66 | Visit catch-connect | |
 | 300GB Prepaid Plan | 300GB | Prepaid | Yes | $28.77 | Visit optus |
Bill Hero is an independent comparison service. We are paid by subscribers and concierge fees, not by carriers or retailers.
Frequently Asked Questions
What is the cheapest 300GB mobile plan on the Optus network?▾
4G 350GB Asia Plan by circles-life at $10.80/mo is currently the cheapest 300GB plan on the Optus network. Prices are updated daily.
Should I choose postpaid or prepaid for a 300GB plan?▾
Postpaid plans typically include handset financing options and are billed monthly. Prepaid plans are pay-as-you-go — better for flexibility and no credit checks. Both are shown in the table above.
How often are mobile plan prices updated?▾
Bill Hero checks mobile plan data daily. All plans shown were validated within the last 24 hours. See the "Prices validated" date above the table for the most recent check.
Can I switch mobile plans without changing my number?▾
Yes. Mobile number portability (MNP) lets you keep your number when switching carriers or networks. The process usually takes 1–2 business days.
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