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.
| Carrier | Plan | Data | Type | 5G | $/mo | Updated | Actions | |
|---|---|---|---|---|---|---|---|---|
 | Red Annual $139 | 24GB | Postpaid | No | $11.42 | Switch — $25 | ||
 | 30GB Mobile | 30GB | Postpaid | Yes | $15.00 | Switch — $25 | ||
| 30GB | 30GB | Postpaid | No | $15.00 | Switch — $25 | ||
| 30GB | 30GB | Postpaid | Yes | $15.00 | Switch — $25 | ||
 | LycaPlan XS | 20GB | Prepaid | Yes | $21.43 | Visit lycamobile | ||
 | 25GB | 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 | ||
| Red $24.90 | 20GB | Postpaid | No | $24.90 | Switch — $25 | ||
 | Small Plan | 25GB | Postpaid | No | $25.00 | Switch — $25 | ||
 | 25GB | 25GB | Postpaid | Yes | $25.00 | Switch — $25 | ||
 | Small 25GB | 25GB | Postpaid | No | $25.00 | Switch — $25 | ||
 | Lifestyle Mobile - Starter | 27.5GB | Postpaid | Yes | $25.00 | Switch — $25 | ||
 | 25GB | 25GB | Postpaid | Yes | $25.00 | Switch — $25 | ||
 | Prepaid 30 Day 22GB | 22GB | Prepaid | No | $25.00 | Visit woolworths-mobile | ||
 | $25 SIM Plan | 25GB | Prepaid | Yes | $26.79 | Visit lebara | ||
 | 30GB Mobile Plan | 30GB | Postpaid | Yes | $29.00 | 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 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 updates mobile plan data daily from the billhero-telco-scraper. Each row shows its last verified date.
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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