Copywriting Agency: Website, Landing Page, Email and Ad Copy That Converts

Updated September 2026 · Written and maintained by the Progression Agency strategy team

A copywriting agency writes the words that sell: website and landing page copy, product descriptions, email sequences, ad copy, sales pages and brand messaging, grounded in research on the buyer and measured by conversion. Creative copywriting has a place in that mix, mostly in headlines and brand lines, as long as the idea still points the reader at the offer. A copywriting firm, a bench of copywriting experts and a source of copywriting consulting all face one test: who researches the buyer before a word is drafted. Progression Agency is a copywriting agency in New York serving businesses across the United States and worldwide. This page explains what conversion copywriting involves, how copy is researched, which copy types we produce, how copy is tested, what a copywriting company should deliver, and what it costs.

What conversion copywriting involves

Conversion copy is written to move a reader to a defined action on a specific page. It starts with who the reader is and what they already believe, states the outcome they want, shows proof, answers objections and asks for the next step. It is edited for clarity and scanning, and it is measured. Our copywriting services page covers the SEO and content side; this page covers the agency engagement for conversion copy.

Copy types we write

Email copywriting services are usually briefed per sequence, while ad copywriting services are briefed per campaign, often with several variants at once. Landing page copywriting services start from one offer and its objections, and sales copywriting services push further into price and proof on a longer page. Blog copywriting services run at higher volume, so a style guide matters; ecommerce copywriting services need the same discipline across a large catalog of product descriptions.

SEO copywriting services

Pages that have to rank and sell at once, mainly service, category and product pages, are the scope here. The writer works from what the searcher wants to know, then shapes the title, heading, opening lines and answers around it without losing the argument for buying.

An SEO copywriting agency should show you a page before and after, and explain each change in terms of what the reader gains. Long articles and blog programs are a different purchase with a different brief. When you speak to an SEO copywriting company, ask who owns the facts on the page, since a writer can only rewrite what your team has confirmed.

Website copywriting services

The home page, service or product pages, about, pricing and the path to getting in touch: these are the pages that do the selling. The work starts before the first draft, with a page-by-page map of what each visitor needs to decide and what evidence would settle it. A SaaS copywriter gives the pricing page its own brief, because the visitor there is comparing plans rather than learning what the product does.

A website copywriting agency should expect headlines and sections to change once a designer sees how long they run, so build a round for that into the plan. Ask a web copywriting agency to leave you the messaging document as well as the pages, because whoever updates the site next year will need the reasoning behind the words.

Research before writing

Every engagement begins with voice-of-customer research: interviews with recent buyers, review mining, sales call recordings, support tickets and search queries. The phrases buyers use become the copy’s vocabulary; the objections they raise become its structure. Drafts are delivered with the research so the client can see where each claim came from.

Writing for the page’s job

A page that must rank needs headings that match queries and depth that answers them; a page that must convert paid traffic needs message match and a single call to action; an email needs one job per message. We write to the job and say when a page is being asked to do two things at once, which usually means two pages. Digital copywriting also has to survive a phone screen, so the point needs to land before the reader’s thumb moves on.

Testing copy

Where traffic allows, headlines, offers and calls to action are tested with defined read dates and decision rules. Where it does not, we use research and the results of comparable pages. Wins are documented in the messaging library so they carry across channels. Our growth marketing page covers the testing loop.

Copy for regulated industries

Healthcare, finance, legal and supplements carry claim rules. Copy is written to the client’s regulatory guidance and reviewed by the client before publication; we flag claims that need substantiation and we do not write guarantees. Medical copywriting services depend on a clinical reviewer who signs off each claim before design begins. Legal copywriting services need an attorney at the firm to check statements about experience against the advertising rules where it practices. Real estate copywriting services have their own limit, because the federal Fair Housing Act bars housing ads that state a preference or limitation based on protected characteristics.

Copy and AI assistants

Pages that state what a product is, who it is for and what it costs in plain language are the pages assistants cite when buyers ask. Conversion copy that is specific serves both the reader and the model; vague copy serves neither.

Working with designers and developers

Copy is written with the layout in mind and delivered in a wireframe so that headings, proof and calls to action land where the eye goes. We work with your design team or ours; website design and development covers the build side.

What a copywriting agency delivers

1. Research summary: interviews, review mining, phrase library.
2. Messaging document: positioning, audience, objections, voice.
3. Copy drafts in wireframes, per page or sequence, with rationale.
4. Revisions within an agreed number of rounds.
5. Test plan where traffic allows.
6. Handover: messaging library the team can reuse.

How to choose a copywriting agency

• Ask to see the research behind a draft they wrote.
• Ask how they write differently for pages that rank versus pages that convert.
• Ask how copy is tested and what was learned.
• Ask how regulated claims are handled.
• Ask who owns the copy and the research. You must.

Copywriter companies usually have more capacity than freelance copywriting services, and someone to cover a sick day. On copywriting, outsource only after you have asked who edits the drafts; professional copywriting services should have a ready answer. A B2B copywriting agency should be able to quote your buyer’s objections back to you, and a SaaS copywriting agency should also know how a trial signup differs from a demo request.

What it costs: copywriting

Email and content work is priced per deliverable or as a monthly program. For copywriting, the price bands below are from our marketing agency pricing guide; a quote follows a list of flows, segments and the volume of content each month.

Every figure above is a price band already published on this site; the quote for copywriting follows a written scope, and the same ranges apply across the United States and worldwide. Small business copywriting services usually cost less because the scope is smaller, often a home page, a few service pages and one email sequence, rather than because the writing takes less care.

Related services and guides

Pages on this site that sit next to copywriting and that a buyer usually reads alongside it.

• Copywriting services
• Content marketing agency
• Growth marketing agency
• Website design and development
• Email marketing
• Branding agency

Frequently asked questions