Can an SEO company optimize for voice search?
Yes, but the honest version of the service is smaller than a separate price tag suggests. The work that helps a page answer a spoken question overlaps heavily with ordinary SEO done well: content built around the questions people actually ask, answers that come first and stand on their own, and accurate local information. The one piece of markup Google documents specifically for content read aloud has a narrow reach, and a company that sells voice optimization as a separate discipline should be able to explain exactly what it would do that its regular work does not.
What the work involves
People speaking to a device can phrase a search as a full question. A company researching voice queries is really researching the questions your customers ask, in their own words, and then making sure your pages answer them.
That has practical consequences for how pages are written. Each question gets a heading that reads the way someone would ask it, followed immediately by a direct answer that makes sense on its own, without the paragraphs around it. Detail and context can follow for readers who want more. This is good writing for any reader, which is why it overlaps so much with the rest of SEO.
For a business people look for nearby, the local information matters as much as the content: a complete and accurate Business Profile and consistent business details wherever the business is listed.
The markup Google documents for reading aloud
Google’s speakable structured data documentation describes markup that “identifies sections within an article or webpage that are best suited for audio playback using text-to-speech.” Before anyone adds it to your site, three limits are worth knowing. The page states that “this feature is in beta and subject to change.” It says that “the speakable property works for users in the U.S. that have Google Home devices set to English, and publishers that publish content in English.” And it is framed around news: its purpose is for “news content to be eligible as answers to topical news queries.”
For a business that does not publish news, speakable markup does little. A company should tell you that rather than add it to your pages for show.
What to be careful with
Proposals for voice search sometimes include figures, such as an ideal answer length in words or the share of searches that are spoken, without saying where they come from. Ask for the source of any number like that.
Ask too how the company will measure results. If it cannot show you a report that separates spoken searches from typed ones, any claim of voice-specific gains is hard to verify, and the honest measure is the performance of the pages and questions it worked on.
Is it worth asking for
Voice optimization need not be bought as a separate project. If your SEO company already writes content around real questions, puts the answer first, and keeps your local information accurate, the core of the work is already being done. The useful question for a proposal that lists voice search as an extra is simple: what will you do differently, and how will we know it worked?