To mask your cell phone number, use *67 before dialing for a free one-time block, or activate a prepaid line for a permanent second number. The average monthly cost of a prepaid plan is around $25, while postpaid add-on lines can cost $30–$50 including taxes and fees. Choose based on your privacy needs and budget.
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Compare Plans →Free to compare · No credit check to browse · Affiliate-supportedFree Methods: *67 and Carrier Settings
The simplest way to mask your cell phone number is to dial *67 before the number you are calling. This free feature, mandated by the FCC for all landline and wireless providers, blocks your caller ID for that single call. It works on most major networks but does not apply to text messages or voicemails. You can also enable permanent caller ID blocking through your phone's settings or by contacting your carrier, though some recipients may still see “Blocked” or “Unknown.”
For occasional use, *67 is the most cost-effective option — it costs $0 and requires no additional plan or app. However, it is not a permanent solution, and some toll-free numbers or emergency services may override the block.
Prepaid Lines: Low-Cost Permanent Masking
If you need a permanent second number for privacy — for online sales, dating, or business — a prepaid line is the most affordable recurring option. Budget providers offer plans starting at $15–$30 per month with limited data, while major carriers’ prepaid brands average $25/month (FCC 2025 data). In contrast, adding a postpaid line to an existing family plan typically costs $30–$50/month after taxes and fees.
| Method | Monthly Cost | Taxes & Fees | Pros | Cons |
|---|---|---|---|---|
| *67 (per call) | $0 | None | Free, no setup | Not permanent, no texts |
| Prepaid line | $25 avg. | ~5% | Permanent, low cost, no contract | Separate device or eSIM needed |
| Postpaid add-on line | $40 avg. | ~20% | Integrated with primary bill | Higher total cost, contract often required |
Prepaid plans also avoid long-term contracts, making them ideal for temporary masking needs. The total annual cost for a prepaid line is roughly $300 versus $480 for a postpaid add-on, according to Consumer Expenditure Survey averages.
App-Based Masking: Costs and Trade-offs
Several third-party privacy apps offer temporary phone numbers for calls and texts. These apps typically charge $5–$10 per month for a virtual number, with some offering pay-per-use options. While convenient, they rely on VoIP technology and may not support 911 calls or short codes (e.g., bank verification).
- Pros: No extra SIM, easy to switch numbers, often includes voicemail and text forwarding.
- Cons: Monthly fee, potential call quality issues, and limited reliability for emergency services.
For users who only need occasional masking, an app can be cheaper than a prepaid line, but for regular use, a prepaid plan offers better reliability at a similar price point.
Taxes and Fees: Prepaid vs Postpaid
One overlooked cost difference is the tax and fee burden. According to the Tax Foundation, prepaid wireless plans face an average effective tax rate of about 5.4%, while postpaid plans are taxed at roughly 19.2%. This gap arises because prepaid plans are often exempt from state Universal Service Fund contributions and certain regulatory fees.
Typical fees include:
- Federal Universal Service Fund (postpaid only, ~10% of bill)
- State and local sales taxes
- E911 surcharges
- Regulatory and administrative fees
For a $25 prepaid plan, total taxes and fees add about $1.35. For a $40 postpaid add-on, they add roughly $7.68 — a significant difference over a year.
Choosing the Right Option for Your Budget
Your choice depends on how often you need to mask your number and your willingness to manage a second line:
- Occasional use (few times a month): Use *67 — it’s free and requires no commitment.
- Frequent masking (weekly): A prepaid line at ~$25/month offers a permanent second number with low taxes.
- Business or high-volume use: A prepaid line is still cost-effective; an app may work if you need multiple numbers temporarily.
- Budget constraint: Avoid postpaid add-ons unless you already have a family plan; the tax savings alone make prepaid cheaper.
Annual cost comparison: *67 = $0; app = $60–$120; prepaid = $300; postpaid add-on = $480. For most users, a prepaid line strikes the best balance between cost and reliability.