What's the realistic timeline and cost for an agency to rebuild a mid-market storefront on Horizon from an existing Dawn-based theme?
No published figure exists. Here is the honest answer
A rebuild from Shopify's Dawn theme to Horizon has no published benchmark price; the one published timeline we found is about two months (Shopify's Dermalogica case study, October 2026). That skin care brand's Dawn theme was 60% custom code. Moving to Horizon means switching themes, so section settings and code edits don't carry over (Shopify Help Center, October 2026).
- Published price benchmark
- None found for this rebuildShopify's Dermalogica case study, the one published Dawn to Horizon example we found, gives a timeline and no project cost (Shopify, October 2026).Source: Shopify (Switching to Horizon theme drives conversion and saves money for Dermalogica)
- Published timeline
- About two months (Dermalogica)With an external developer, from a Dawn theme that was 60% custom code; Dermalogica launched on Horizon on 1 September 2025 (Shopify, October 2026).Source: Shopify (Switching to Horizon theme drives conversion and saves money for Dermalogica)
- Record estimate, section library
- 8 to 12 weeksThe theme section library record's illustrative estimate for 15 to 25 sections with brand tokens and marketing enablement, the shape a Horizon rebuild should take (October 2026).Source: Deploi Build vs. Buy (Shopify Theme Sections: Buy Premium or Build a Section Library?)
- Survives the theme switch
- Products, collections, menus, pages, blog postsSection and block settings, global settings, text, code edits and templates belong to each theme and are set up again in Horizon (Shopify Help Center, October 2026).Source: Shopify Help Center (Adding, previewing, and buying themes)
Deploi’s call
Plan the move from Shopify's Dawn theme to its Horizon themes as a section library build that happens to land on Horizon, not as a theme migration. The theme section library record's illustrative estimate for that build is 8 to 12 weeks. The rebuild is unavoidable either way. The difference between the two framings is whether you own reusable parameters at the end, or a second snapshot that will need the same conversation in two years.
BuildRebuild on Horizon as a section library when
- Your Dawn theme is mostly custom code and campaign pages need developer tickets, the state Shopify's Dermalogica case study describes (Shopify, October 2026).
- Marketing ships new campaign or landing pages at least monthly with a developer in reach, which Deploi's theme section library record scores BUILD (October 2026).
- A redesign is due anyway, so the new art direction and the new base ship once.
WaitStay on Dawn for now while
- Dawn takes its updates cleanly; Shopify shipped Dawn 16.1.0 on 9 October 2026 (Shopify Theme Store, October 2026).
- A replatform or an enterprise resource planning (ERP) cutover lands in the same window.
- The only argument is that Horizon is newer, with no section model planned on top.
Basis: Shopify Theme Sections: Buy Premium or Build a Section Library?, our Build vs. Buy decision record, scored BUILD.
Is moving from Dawn to Horizon a theme update or a rebuild?
Moving from Shopify's free Dawn theme to its Horizon themes is a rebuild, not a theme update. Shopify's update flow adds a newer version of the same theme to your drafts and copies your theme editor changes into it (Shopify Help Center, October 2026). Horizon is a different theme family. Shopify names themes that support theme blocks, "including the Horizon family of themes," as its latest theme architecture (Shopify Help Center, October 2026). Theme blocks are reusable pieces that work across sections and nest inside each other (Shopify developer docs, October 2026).
Dawn keeps its own version line: Shopify shipped Dawn 16.1.0 on 9 October 2026 (Shopify Theme Store, October 2026). So the move means installing Horizon and rebuilding the storefront inside it, which makes the point where customizing a theme stops paying the question to settle first.
Is there a published price or timeline for a Dawn to Horizon rebuild?
No published benchmark prices a Dawn to Horizon rebuild, and the one published timeline we found is about two months. Shopify's case study of Dermalogica, a skin care brand on Shopify Plus, describes a Dawn theme that "had become 60% custom code" (Shopify, October 2026). With an external developer, the move took "about two months total, in between day-to-day projects". Dermalogica launched on Horizon on 1 September 2025, and the developer estimated Horizon got the site "almost 90% of the way there out of the box".
Deploi's theme section library record gives 8 to 12 weeks as its illustrative estimate for the project a Horizon move should be (October 2026). That project is 15 to 25 sections with brand tokens, meaning shared type, color and spacing settings, plus marketing enablement. For price, compare quotes line by line, so each agency itemizes the line items a migration quote should carry.
What does a Dawn to Horizon rebuild timeline consist of?
A Dawn to Horizon rebuild for one storefront runs in six phases, and the five that run in sequence add up to about 7 to 12 weeks in Deploi's estimates. Art-directed systems run alongside the template rebuild, so a second developer keeps them off the critical path.
| Phase | Weeks | What happens |
|---|---|---|
| Discovery and section inventory | 1 to 2 | List every Dawn section and its real usage; unused sections are deleted, not rebuilt |
| Brand tokens and Horizon setup | 1 to 2 | Shared type scale, colors, spacing and block defaults, set before any section |
| Core template rebuild | 3 to 5 | Home, collection, product, cart, search, account and content templates |
| Art-directed systems | 2 to 4, alongside templates | Hero and banner system, merchandising rails |
| App re-activation and testing | 1 to 2 | Every app block and app embed added again and retested |
| Marketing enablement and handover | 1 | Training that decides whether the build survives the campaign calendar |
What carries over from Dawn to Horizon, and what has to be rebuilt?
Store data carries over from Dawn to Horizon, and everything stored in the theme has to be rebuilt. Shopify says a store's "products, collections, menus, pages, blog posts aren't changed or deleted when you switch to a new theme, because they're managed in the Admin" (Shopify Help Center, October 2026). The same Help Center page lists what belongs to each theme and must be set up again:
- The settings applied to sections and blocks
- Global theme settings, including colors and fonts
- Text and wording
- Code customizations, including code an app added
- Available theme templates
Apps stay installed, but after you change your published theme, "you'll need to re-activate those apps in your new theme as they won't be active by default" (Shopify Help Center, October 2026). Metafields are Shopify's custom data fields on products, customers and orders, and their values stay in the admin (Shopify Help Center, October 2026). So you reconnect them in Horizon's theme editor rather than re-enter them.
What moves the cost of a Dawn to Horizon rebuild?
Five drivers move the cost of a Dawn to Horizon rebuild, and in our judgment the biggest is where your content lives:
- Content in section settings. Copy typed into a Dawn section is re-entered by hand, while content in metafields and metaobjects (Shopify's structured content entries) only needs reconnecting.
- Port or redesign. A like-for-like port sits at the low end; new art direction sits at the top, because it is a different project on the same ticket.
- Art-directed systems. Each hero and banner system or set of merchandising rails is its own build inside the rebuild.
- App count. Every app block and embed is re-activated and retested, so the number of apps you run shows up in the quote.
- Marketing training. Skipping enablement saves a week and costs a quarter.
Apps the new theme replaces offset the bill. Shopify's case study credits Horizon's native personalization, search and page builder with eliminating over £30,000 ($39,000) a year of Dermalogica's costs (Shopify, October 2026).
When should you stay on Dawn instead of rebuilding on Horizon?
Stay on Dawn when the rebuild's only case is that Horizon is newer, because Dawn is still maintained. In our judgment, a like-for-like port buys architecture you won't feel for a year. Deploi's phase estimates also assume one storefront, one language and no checkout, enterprise resource planning (ERP) or search replatform in the same window. Multi-market and business-to-business (B2B) storefronts sit above them.
Deploi’s point of view
Our own position, from building on Shopify. Kept apart from the sourced facts above.
- Where we disagree
- The pitch for Horizon is usually performance and modern architecture. Theme blocks are genuinely better to build on, but no theme swap fixes a merchandising problem by itself, and a like-for-like port to Horizon buys architecture you will not feel for a year.
- What we tell clients to do first (Deploi judgment)
- Count section usage before porting anything. Sections used once or never get deleted, not rebuilt, which makes discovery the cheapest cost cut in the project, and it only happens if someone is paid to count usage rather than to port the list.
- What this page adds
- The parent answer decides when customizing a theme stops paying; this one prices the move to Horizon: why it is a rebuild rather than an update, the one published timeline, the phases behind it, and exactly which store data survives the theme switch.
Decision records behind this answer
When this answer changes
- Shopify ships an update path from Dawn to Horizon, which would turn the rebuild into an update.
- Shopify stops shipping Dawn versions; the latest is Dawn 16.1.0, released 9 October 2026.
- Shopify or a merchant publishes another Dawn to Horizon timeline or price.
- Horizon ships a major version that changes its settings, as Horizon 4.0.0 did with color palettes in June 2026.
- Deploi's theme section library record changes its 8 to 12 week estimate.
Related questions
This follows from At what point does customizing an existing Shopify theme stop being cost-effective compared to commissioning a custom build?
- How much custom development budget should a $20M-$500M merchant expect to set aside annually just for ongoing theme customization, separate from the initial build?
Ongoing theme customization takes two budget lines: upkeep at 15 to 20% of build cost yearly, and new work sized from the campaign calendar.
- At what point does a premium paid theme (versus Dawn or Horizon free defaults) actually earn its cost for a $20M-$500M merchant?
A premium Shopify theme earns its cost at $20 million to $500 million as the base for custom work, never the finished storefront.
- What line items typically make up a full Shopify Plus migration quote (discovery, design, dev, QA, training, post-launch support)?
A Shopify Plus migration quote has six line items, not one price: discovery, design, development, quality assurance (QA), training and post-launch support.
- How many apps is 'too many' for a mid-market Shopify store before performance and manageability start to suffer?
Ten apps that load storefront code is the practical performance ceiling for a mid-market Shopify store, because other apps cost no load time.
Sources
Every figure on this page traces to one of these. Official and vendor pages are checked on the date shown; Deploi records are our own published decisions.
- Shopify, Switching to Horizon theme drives conversion and saves money for Dermalogica
- Shopify Help Center, Adding, previewing, and buying themes
- Shopify Help Center, Updating themes
- Shopify Help Center, Theme architecture versions and sources
- Shopify Theme Store, Dawn
- Shopify Help Center, Extend your theme with apps
- Shopify Help Center, Metafields
- Shopify developer docs, Blocks
- Deploi Build vs. Buy, Shopify Theme Sections: Buy Premium or Build a Section Library?