Cheapest 20GB Mobile Plans — Any Network
The cheapest 20GB mobile plan across all networks is Red Annual $139 by cmobile at $11.42/mo.
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Forward your bill20 Plans — sorted by price
Showing plans with 20–30GB data across all networks. Postpaid and prepaid only.
Prices validated: 25 June 2026
| Carrier | Plan | Data | Type | 5G | $/mo | Actions | |
|---|---|---|---|---|---|---|---|
 | Red Annual $139 | 24GB | Postpaid | No | $11.42 | Switch — $25 | |
 | 30GB | 30GB | Postpaid | No | $15.00 | Switch — $25 | |
| 30GB Mobile | 30GB | Postpaid | Yes | $15.00 | Switch — $25 | |
| 30GB | 30GB | Postpaid | Yes | $15.00 | Switch — $25 | |
 | 25GB SIM Only Plan | 25GB | Postpaid | Yes | $22.00 | Switch — $25 | |
 | Starter | 29GB | Prepaid | No | $23.90 | Visit yomojo | |
| Starter | 29GB | Prepaid | No | $23.90 | Visit yomojo | |
 | 20GB 5G SIM Plan | 20GB | Postpaid | Yes | $24.00 | Switch — $25 | |
 | 30GB | 30GB | Postpaid | Yes | $24.80 | Switch — $25 | |
| 30GB | 30GB | Postpaid | Yes | $24.80 | Switch — $25 | |
 | 30GB Mobile Plan | 30GB | Postpaid | Yes | $24.90 | Switch — $25 | |
| Red $24.90 | 20GB | Postpaid | No | $24.90 | Switch — $25 | |
 | 25GB Mobile Plan | 25GB | Postpaid | Yes | $25.00 | Switch — $25 | |
 | Lifestyle Mobile - Starter | 27.5GB | Postpaid | Yes | $25.00 | Switch — $25 | |
 | 25GB Plan | 25GB | Postpaid | Yes | $25.00 | Switch — $25 | |
 | Prepaid 30 Days 22GB | 22GB | Prepaid | No | $25.00 | Visit woolworths-mobile | |
 | 22GB Data 28 Days | 22GB | Prepaid | No | $26.79 | Visit coles-mobile | |
 | $25 SIM Plan | 25GB | Prepaid | Yes | $26.79 | Visit lebara | |
 | $29 5G Mobile Plan | 29GB | Prepaid | Yes | $29.00 | Visit aldi-mobile | |
 | 29GB Prepaid Plan | 29GB | Prepaid | Yes | $29.00 | Visit ezee-mobile |
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 20GB mobile plan across all networks?▾
Red Annual $139 by cmobile at $11.42/mo is currently the cheapest 20GB plan across all networks. Prices are updated daily.
Should I choose postpaid or prepaid for a 20GB 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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