Cheap Telstra Network Mobile Plans Under $20

In our database, 16 mobile plans from 10 providers currently have an advertised price of $20 a month or less on the Telstra network. That includes plans sold directly by Telstra as well as resellers running on Telstra's infrastructure, such as Boost Mobile, Belong, ALDI mobile, Cmobile, Everyday Mobile, JB Hi-Fi, More Telecom, Tangerine Telecom and Telsim. Only 4 of the 16 keep that price with no promo hike -- the other 12 are introductory offers that revert to a higher regular price once the promo period ends, in some cases nearly tripling. Billing cycles also range from 7 to 365 days, so we've included the monthly-equivalent figure (calculated as price × 30 ÷ billing days) alongside every price. We've split the plans into two groups below: data-only plans (no talk & text included) and normal plans (talk & text included), since they're not really comparable to each other. Before you sign up, it's worth checking your address against our Telstra mobile coverage map, since every plan on this page depends on that same network regardless of which brand it's sold under.

*ALDI mobile's $2.00 plan is a pay-as-you-go activation SIM valid for 365 days -- it doesn't include any bundled data or talk & text. It's genuinely $2.00 long-term (≈$0.16/mo equivalent), just without inclusions.

**"No promo hike" only means the raw per-cycle price doesn't change on renewal -- it says nothing about whether that cycle is a good monthly deal. Boost Mobile's 7 Day Expiry plan below is genuinely priced with no promo but still works out to $60/month equivalent once normalized -- check the monthly equivalent column before comparing plans on different cycles.

Data-only plans (4)

No talk & text included. Sorted by current price, lowest first.

Normal plans, talk & text included (12)

Sorted by current price, lowest first; ties broken by cost per GB, best value first. Highlighted rows keep their per-cycle price long-term with no promo hike.

Worth a second look: Telstra's own Casual Pre-Paid SIM Only Mobile Plan bills every 182 days, so its $15.00 current price works out to just ≈$2.47/month equivalent -- the lowest monthly-equivalent figure of any talk & text plan on this page. But it only includes 1GB of data and 120 minutes of calls, so it suits very light, occasional use rather than a primary SIM.

Genuinely $20-or-under, by network speed

Only the 4 plans that stay at their listed price long-term (no promo hike) are included here, split by whether they support 5G or are 4G-only.

5G-capable (2 plans)

4G (1 plan)

ALDI mobile's $2 Pay As You Go Prepaid Mobile Plan (365 days, Telstra) isn't shown above -- it's an activation-only SIM with no bundled data, so our data source doesn't specify a network speed for it.

Providers compared

All 16 plans below run on the Telstra network, whether sold directly by Telstra or by a reseller. Telstra, Boost Mobile and Tangerine Telecom each have more than one plan under $20 in our database.

The remaining 7 providers -- ALDI mobile, Belong, Cmobile, Everyday Mobile, JB Hi-Fi, More Telecom and Telsim -- each have one plan under $20 in our database.

Frequently asked questions

Prices and data allowances shown are current in our database as of July 2026 and reflect advertised carrier pricing at time of listing. Where a plan has an introductory promo, we show both the current and regular price. Monthly-equivalent figures are calculated as price × (30 ÷ billing days) and are provided for comparison purposes only -- they do not represent an actual monthly billing amount for plans that don't bill monthly. Plans, prices and inclusions change frequently, and details are entered into our database manually so errors are possible -- we do not guarantee the accuracy of any price, allowance, or other detail shown. Always confirm the final price, billing cycle, and all plan information directly with the carrier before signing up.