Cheapest 40GB Mobile Plans on Optus
The cheapest 40GB mobile plan on the Optus network is 40GB 5G SIM Plan by southern-phone at $29.00/mo.
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Forward your bill14 Plans — sorted by price
Showing plans with 40–60GB data on the Optus network. Postpaid and prepaid only.
Prices validated: 25 June 2026
| Carrier | Plan | Data | Type | 5G | $/mo | Actions | |
|---|---|---|---|---|---|---|---|
 | 40GB 5G SIM Plan | 40GB | Postpaid | Yes | $29.00 | Switch — $25 | |
 | 50GB SIM Only Plan | 50GB | Postpaid | Yes | $29.00 | Switch — $25 | |
 | Essential | 42GB | Prepaid | No | $29.90 | Visit yomojo | |
| Essential | 42GB | Prepaid | No | $29.90 | Visit yomojo | |
 | 40GB Mobile Plan | 40GB | Postpaid | Yes | $30.00 | Switch — $25 | |
 | 40GB | 40GB | Postpaid | Yes | $33.80 | Switch — $25 | |
| 40GB | 40GB | Postpaid | Yes | $33.80 | Switch — $25 | |
 | Lifestyle Mobile - Essential | 40GB | Postpaid | Yes | $35.00 | Switch — $25 | |
 | 75GB 28 Day Plan | 42GB | Prepaid | Yes | $37.50 | Visit amaysim | |
 | Value 40gb | 45GB | Postpaid | Yes | $40.00 | Switch — $25 | |
| Value 40GB | 40GB | Postpaid | Yes | $40.00 | Switch — $25 | |
 | 45GB Prepaid Plan | 45GB | Prepaid | Yes | $41.79 | Visit optus | |
| 50GB Prepaid Plan | 50GB | Prepaid | Yes | $42.86 | Visit optus | |
 | 40GB Data | 40GB | Postpaid | No | $55.00 | 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 40GB mobile plan on the Optus network?▾
40GB 5G SIM Plan by southern-phone at $29.00/mo is currently the cheapest 40GB plan on the Optus network. Prices are updated daily.
Should I choose postpaid or prepaid for a 40GB 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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