Cheapest 80GB Mobile Plans on Optus
The cheapest 80GB mobile plan on the Optus network is Optus Flex Plus 140GB by optus at $29.03/mo.
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Forward your bill17 Plans — sorted by price
Showing plans with 80–120GB data on the Optus network. Postpaid and prepaid only.
Prices validated: 25 Sept 2026
| Carrier | Plan | Data | Type | 5G | eSIM | $/mo | Actions | |
|---|---|---|---|---|---|---|---|---|
 | Optus Flex Plus 140GB | 90GB | Prepaid | Yes | Yes | $29.03 | Visit optus | |
 | 80GB 5G SIM Plan | 80GB | Postpaid | Yes | — | $34.00 | Switch — $25 | |
 | Pro | 105GB | Prepaid | No | Yes | $34.90 | Visit yomojo | |
 | 100GB SIM Only | 100GB | Postpaid | Yes | Yes | $35.00 | Switch — $25 | |
 | 80GB | 80GB | Postpaid | Yes | Yes | $40.00 | Switch — $25 | |
 | 80GB 28 Day SIM Plan | 80GB | Prepaid | Yes | Yes | $42.86 | Visit amaysim | |
 | Medium 80GB | 80GB | Postpaid | Yes | Yes | $45.00 | Switch — $25 | |
 | 5G Medium | 100GB | Postpaid | Yes | — | $45.00 | Switch — $25 | |
 | $15, 100GB Data, 30 days | 100GB | Prepaid | Yes | — | $45.00 | Visit coles-mobile | |
| 250GB 28 Day SIM Plan | 95GB | Prepaid | Yes | Yes | $48.21 | Visit amaysim | |
 | Essential 100gb | 100GB | Postpaid | Yes | — | $50.00 | Switch — $25 | |
 | Lifestyle Mobile - Plus | 100GB | Postpaid | Yes | Yes | $50.00 | Switch — $25 | |
| Essential 100GB | 100GB | Postpaid | Yes | Yes | $50.00 | Switch — $25 | |
| 120GB 28 Day SIM Plan | 120GB | Prepaid | Yes | Yes | $53.57 | Visit amaysim | |
 | 100GB | 100GB | Postpaid | No | — | $54.90 | Switch — $25 | |
| Premium 120GB | 120GB | Postpaid | Yes | — | $60.00 | Switch — $25 | |
 | 80GB Data | 80GB | Postpaid | No | — | $65.00 | Switch — $25 |
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 80GB mobile plan on the Optus network?▾
Optus Flex Plus 140GB by optus at $29.03/mo is currently the cheapest 80GB plan on the Optus network. Prices are updated daily.
Should I choose postpaid or prepaid for a 80GB 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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