AI Voice for Ads: Cost, Rules and Script Length (2026)

An AI voice can work for ads if your plan includes commercial use, the voice does not imitate a real person without permission, and the script fits the spot. On Starter and above, commercial use is included. A 30-second spot fits about 75 words, and disclosure rules depend on the medium and the market.

Can you use an AI voice in a commercial?

Commercial use depends on the plan you buy, not only on the voice. Free tiers often exclude it. Prices and terms as of October 17, 2026:

| Provider | Free plan commercial use | Paid plan commercial use | |---|---|---| | ElevenLabs | No | Yes, from Starter | | Cartesia | No | Yes, from Pro at $5 a month | | WellSaid Labs | No (the trial has no commercial rights) | Yes, on paid plans | | OndaLabs | No; the Free plan is for auditioning | Included from Starter at $9 a month |

Read the license for the plan you actually buy. A commercial license covers the provider's terms. It does not clear an ad for broadcast or for a particular ad network, so check each outlet's rules too.

How many words fit a 15, 30 or 60 second ad?

Radio production guidance is the most useful starting point. The working ranges below come from Killer Spots, a radio production company, which gives body-copy ranges that differ slightly from its FAQ.

| Spot length | Words (working range) | Notes | |---|---|---| | :10 | 22 to 28 | One message and one call to action | | :15 | 35 to 40 | Tight, with room for a tag line | | :30 | 70 to 80 | Killer Spots warns that past 80 words "the pauses disappear" | | :60 | 140 to 160 | Room for a story and a full offer |

Killer Spots uses about 2.5 words per second for a professional conversational read, about 2.2 for a slow, warm read, and up to about 3 for fast copy. A two-voice 30-second dialogue fits about 65 to 70 words. Breadnbeyond uses the same 2.5 words per second, but that figure comes from its own experience rather than a study.

Voices differ in pace. Microsoft's documentation lists words-per-minute values per voice that range from 139 to 293 across languages. Time a draft render before you lock the script.

What an ad voiceover costs

Human voice talent for ads is usually priced by usage. Voices.com says broadcast work "is priced by usage: where the ad airs, how long it runs, and the platform." The rate cards below are seller figures, not union scale, and they are as of October 17, 2026.

| Use | Published human rate | Source | |---|---|---| | Social ad, 15 to 30 seconds | $80 to $300 flat fee | VoiceBros | | Online pre-roll | $120 to $400 | VoiceBros | | Local radio, 30 seconds | $200 to $600 | VoiceBros | | Local TV, 3-month use, US local market | $400 to $500 | Voice Crafters | | Local TV, 12-month use, US local market | $1,200 to $1,500 | Voice Crafters |

AI voice costs are much lower per spot. As of October 17, 2026, a 75-word, 30-second spot is about 450 characters. On Starter that is about $0.024 on Onda Lite and about $0.036 on Onda Flash (derived). That covers the voice only. Music, sound design and media buying cost extra.

Do AI voices work in ads? What the studies show

Two recent studies point in different directions, and both are small or commissioned.

WPP Media (published October 27, 2025). Choreograph NeuroLab and MediaScience tested 55 participants in Chicago, New York and Austin. Listeners rated ads higher when they believed a human voiced them. Synthetic-voice ads still matched human-voiced ads on brand engagement and purchase intent. In this test, 42 percent identified generic AI voices in single sentences and 47 percent in full ads.
Azerion with Differentology (published July 14, 2026). The study surveyed 3,000 UK respondents. Thirty-seven percent believed an AI-voiced ad was human, 29 percent correctly identified the AI ad, and 26 percent thought the human voice was AI. An ad platform commissioned it, so read it with that in mind.

The honest summary is mixed. Test a candidate voice with your own audience before you assume either way.

Consent, disclosure and union rules

Rules differ by country, state and medium. These are the ones we verified as of October 17, 2026:

SAG-AFTRA 2025 Commercials Contracts (US). Using a digital replica of a performer needs 48 hours' notice and consent, and the performer is paid 1.5 scale session fees per commercial that uses the replica. Fully synthetic commercials are negotiated with the union. This applies to replicas of a real performer, not to a generic stock voice. The National Board approved the contracts on April 27, 2025.
New York synthetic performer law. Signed on December 11, 2025 and effective June 9, 2026, it requires advertisements to conspicuously disclose a synthetic performer. Audio-only ads are excluded. Penalties are $1,000 for a first violation and $5,000 for later ones.
Tennessee ELVIS Act. Effective July 1, 2024, it creates civil liability for using a person's voice or a simulation of it in advertising without authorization.
EU AI Act, Article 50. Applies from 2 August 2026. Deployers must disclose deepfakes, meaning content that "would falsely appear to a person to be authentic or truthful," with clear labels.
YouTube's altered content policy. Creators must disclose content that makes a real person appear to say or do something they did not. Cloning your own voice for a voiceover is listed as a minor edit that needs no disclosure. The page does not mention ads.

Do not assume an AI voice ad needs no disclosure. A New York exemption for audio-only ads does not cover audiovisual ads with a synthetic performer.

How to produce an ad voiceover step by step

Lock the length first and set the word count from the table above.
Write for the ear. Use short sentences, put the brand name early and end with one clear call to action.
Audition voices on the Free plan, then move to a paid plan with commercial use before you publish.
Describe delivery in plain words, such as "warm, unhurried, confident," and use expressive tags where the plan supports them.
Render the file and time it. If it runs long, cut words rather than speeding the read.
Check loudness against the broadcaster's or platform's delivery spec. For European broadcast, EBU R128 sets a programme target of -23.0 LUFS and a true-peak limit of -1 dBTP. Other platforms set their own targets.
Keep the license, the voice choice and any consent records with the project file.

Platforms that generate ad voices

Spotify announced Gen AI Ads on April 2, 2025. At that point, advertisers in the US and Canada could produce scripts and voiceovers in Spotify Ads Manager at no additional cost, with the UK to follow. Spotify's help center also describes a free voice-actor option with a turnaround of 2 to 4 business days. We did not verify the current country list for Gen AI Ads as of October 17, 2026.

Where OndaLabs fits

OndaLabs offers text to speech with 30 prebuilt voices that work in every supported language, two-speaker dialogue for a two-voice spot, and Onda Flash, the most expressive model, on paid plans. Custom voices from the Creator plan at $22 a month, which includes 3 custom voices, can be cloned from a recording you have permission to use or designed from a text description. Music generation is included on Creator for a background bed, and image generation on Starter for a companion visual. OndaLabs does not clear its voices for broadcast or ad networks, so check the rules described above.

Start with the text to speech tool, try a two-voice spot in the dialogue tool, and compare plans on the pricing page. For the human side of the budget, read voiceover cost, AI versus human voice actors. For script writing, read how to write a voiceover script.

Frequently asked questions

Can I use an AI voice in a commercial?

Often yes, but only on a plan that includes commercial use. OndaLabs includes it from Starter at $9 a month, while several competitors' free tiers exclude it. Check the license on the plan you buy and the rules of each outlet that will air the ad.

How many words fit in a 30-second ad?

Radio production guidance puts a 30-second spot at about 70 to 80 words. That assumes a conversational pace of roughly 2.5 words per second. Time a draft render, because voices differ in pace.

Do I have to disclose that an ad uses an AI voice?

It depends on where and how the ad runs. New York requires disclosure of synthetic performers in audiovisual ads but excludes audio-only ads. The EU rules concern deepfakes that falsely appear authentic. Check the rules for each market and platform before you publish.

Do AI voiceovers work as well as human voice actors in ads?

The evidence is mixed. The WPP Media study found that synthetic-voice ads matched human-voiced ads on brand engagement and purchase intent, but listeners still rated human-voiced ads higher. Azerion's commissioned survey is one more data point. Test with your own audience.

Is it legal to clone a celebrity's voice for an ad?

Do not do it without permission. Tennessee's ELVIS Act makes using a person's voice or a simulation of it in advertising without authorization a civil wrong. OndaLabs custom voices can only come from a recording you have permission to use, so get written permission before any clone appears in an ad.