Cheapest 20GB Mobile Plans on Telstra
The cheapest 20GB mobile plan on the Telstra network is 30GB by tangerine at $15.00/mo.
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Forward your bill14 Plans — sorted by price
Showing plans with 20–30GB data on the Telstra network. Postpaid and prepaid only.
Prices validated: 25 June 2026
| Carrier | Plan | Data | Type | 5G | $/mo | Actions | |
|---|---|---|---|---|---|---|---|
 | 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 | |
 | Prepaid 30 Days 22GB | 22GB | Prepaid | No | $25.00 | Visit woolworths-mobile | |
 | $29 5G Mobile Plan | 29GB | Prepaid | Yes | $29.00 | Visit aldi-mobile | |
 | 29GB Prepaid Plan | 29GB | Prepaid | Yes | $29.00 | Visit ezee-mobile | |
| 30GB | 30GB | Postpaid | No | $30.00 | Switch — $25 | |
 | Blue $30 | 29GB | Postpaid | Yes | $30.00 | Switch — $25 | |
| Prepaid 30 Days 30GB with 5G | 30GB | Prepaid | Yes | $30.00 | Visit woolworths-mobile | |
 | Easy Mobile 29 | 29GB | Postpaid | Yes | $40.00 | Switch — $25 | |
 | $39 Prepaid SIM | 30GB | Prepaid | Yes | $41.79 | Visit boost-mobile | |
| $39 Prepaid SIM | 30GB | Prepaid | Yes | $41.79 | Visit boost-mobile | |
 | $44 Pre-Paid Mobile Plan EOFY Sale | 20GB | Prepaid | No | $47.14 | Visit telstra | |
| Mobile Bundle Plan | 25GB | Postpaid | Yes | $61.00 | 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 on the Telstra network?▾
30GB by tangerine at $15.00/mo is currently the cheapest 20GB plan on the Telstra network. 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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