WordPress Gutenberg vs ACF Flexible Content: Which Should You Choose?

If you're building custom WordPress websites, you've likely encountered the decision: Should I use Gutenberg (WordPress's native block editor) or Advanced Custom Fields (ACF) Flexible Content? Both allow you to create flexible, modular page layouts, but they take very different approaches.

This comprehensive guide will help you understand the strengths and weaknesses of each, and make the right choice for your projects.

What Are Gutenberg and ACF Flexible Content?

Gutenberg (WordPress Block Editor)

Gutenberg is WordPress's native content editor, introduced in WordPress 5.0 (December 2018). It uses a "block" approach where every piece of content – paragraphs, images, headings, buttons, etc. – is a separate block that can be added, moved, and customized.

Core Concept: Content is built by stacking and arranging pre-defined blocks. Developers can create custom blocks to extend functionality.

Key Features:

Native to WordPress (no plugins required)
Visual, drag-and-drop interface
Growing library of core blocks
Extensible through custom block development
Full site editing (with block themes)
Patterns and reusable blocks

ACF Flexible Content

Advanced Custom Fields is a popular WordPress plugin that allows developers to add custom fields to posts, pages, and custom post types. Flexible Content is a specific field type that lets you create repeatable, flexible sections.

Core Concept: Developers define fields and layouts in code or the ACF interface. Content editors then choose from these pre-defined layouts to build their pages.

Key Features:

Field-based content management
Highly customizable layouts
Clean, structured data storage
Minimal markup overhead
Precise control over output
Works with any theme

Development & Cost Considerations

Gutenberg Development Approach

What it requires:

Gutenberg blocks are built using modern JavaScript frameworks (React). This means your development team needs:

Modern JavaScript/React expertise
Build tools and development environment
Understanding of WordPress block architecture
Time to set up compilation and deployment

Development costs:

Higher initial learning curve if team is PHP-focused
Setup time: 4-8 hours for development environment
Per block development: 6-12 hours for custom blocks
Ongoing maintenance: Updates can break blocks requiring fixes

Team requirements:

JavaScript developer (£400-700/day rates)
Or WordPress developer willing to learn React
Build process management
Version control and deployment expertise

Real-world timeline: Creating 5 custom blocks for a business website: 3-5 days of development

ACF Development Approach

What it requires:

ACF Flexible Content uses traditional PHP development. Your team needs:

WordPress/PHP knowledge (most WordPress developers have this)
Understanding of ACF field system
Basic template development skills
No build process or compilation

Development costs:

Lower learning curve for WordPress developers
Setup time: 1-2 hours
Per layout creation: 2-4 hours for custom layouts
Ongoing maintenance: Very stable, minimal breaking changes

Team requirements:

WordPress developer (£300-600/day rates)
No specialised JavaScript knowledge needed
Simpler deployment process
Less tooling overhead

Real-world timeline: Creating 5 flexible content layouts: 1.5-2 days of development

Cost difference: ACF development typically 40-60% faster for custom WordPress sites.

User Experience Comparison

Editing with Gutenberg

Content Editor Perspective:

Pros:

Visual, WYSIWYG editing
See roughly how page will look while building
Drag and drop blocks to reorder
Familiar if you've used modern page builders
Quick content entry for simple pages
Built-in blocks for common elements

Cons:

Can feel cluttered with many blocks
Block inserter interface can be overwhelming
Sometimes difficult to nest blocks deeply
Block settings in sidebar can be hard to find
Variations between blocks can be confusing

Best For:

Content writers who want visual feedback
Teams already familiar with block editors
Sites with simple, content-focused pages
Projects where seeing layout while editing matters

Editing with ACF Flexible Content

Content Editor Perspective:

Pros:

Clean, form-based interface
Clear structure and organization
Easy to understand what each field does
Consistent experience across sections
Fields can be grouped logically
Less overwhelming for beginners

Cons:

No visual preview while editing
Must preview/publish to see result
Less intuitive initially
Requires more clicks to add sections
Limited rich text editing options

Best For:

Editors comfortable with structured forms
Projects where precise data entry matters
Teams that prefer clear, labelled fields
Sites with complex, data-heavy content

Performance & Long-Term Impact

Website Performance

Gutenberg impact on site speed:

Additional CSS and JavaScript loaded for blocks
More database queries in some cases
Can slow page load if many blocks used
Block markup can be less optimised

ACF impact on site speed:

Minimal frontend overhead (just your content)
Cleaner, leaner HTML output
No block-specific JavaScript required
Better control over performance optimization

Real-world difference: A typical page with 8 content sections:

Gutenberg: 1.8-2.4s page load
ACF: 1.2-1.6s page load

Business impact: Faster pages improve SEO rankings and conversion rates. Even 0.5s matters.

Data Portability

Gutenberg:

Content is more portable between WordPress sites
Easier to move content between themes
Good if you change sites frequently

ACF:

Data is structured and queryable
Easier to migrate to non-WordPress platforms
Better for custom integrations and APIs
Clean data export for other systems

Consider: Are you likely to move away from WordPress eventually? ACF data is easier to migrate to modern platforms like Payload or custom solutions.

Long-Term Maintenance Costs

Gutenberg maintenance reality:

WordPress updates sometimes break custom blocks
Requires developer time to fix issues (£300-800 per incident)
Build process adds complexity to updates
Testing required after WordPress core updates
Annual maintenance: £800-1,500 typically

ACF maintenance reality:

Very stable - rarely breaks with updates
Simpler troubleshooting when issues occur
No build process to maintain
Fewer emergency fixes needed
Annual maintenance: £300-600 typically

5-year cost difference: ACF saves approximately £2,500-4,500 in maintenance costs.

Design Flexibility

What clients often care about: "Can I have exactly the design I want?"

Gutenberg:

Good for standard layouts
Block themes provide consistency
Some design limitations from block structure
Can achieve custom designs, but requires more development

ACF:

Complete design freedom
No constraints from block system
Pixel-perfect custom layouts
Easier to match exact brand guidelines

Business consideration: If you're investing in custom design, ACF better preserves your vision.

Use Case Recommendations

Choose Gutenberg When:

1. Content-First Websites

Blogs and news sites
Content-heavy pages
Writers need visual editing
Standard content patterns

2. Future-Proofing

Want native WordPress solution
Planning for full site editing
Following WordPress direction
Long-term support confidence

3. Client Capabilities

Non-technical clients
Visual learners
Prefer WYSIWYG editing
Already use Gutenberg for posts

4. Development Team

React/JavaScript expertise
Modern frontend skillset
Comfortable with build tools
Want reusable components

5. Plugin Ecosystem

Need many third-party blocks
Want pattern libraries
Benefit from block directories
Community themes and tools

Choose ACF Flexible Content When:

1. Complex, Data-Driven Sites

E-commerce catalogs
Directory listings
Review/comparison sites
Data needs to be queried

2. Precise Design Requirements

Custom, bespoke designs
Exact markup control needed
Performance is critical
Minimal frontend overhead

3. Development Team

PHP/WordPress expertise
Prefer traditional development
Don't want build process
Comfortable with templates

4. Client Capabilities

Prefer form-based editing
Need clear, labelled fields
Better with structure
Don't need visual preview

5. Legacy or Compatibility

Existing ACF sites
Must support older WordPress
Large ACF code base
Team knows ACF well

The Hybrid Approach: Best of Both Worlds

You don't have to choose one exclusively. Many smart developers combine both:

Option 1: ACF Blocks (ACF Pro Feature)

What it is: ACF Pro offers "ACF Blocks" - you get Gutenberg's visual interface but build blocks using ACF's field system instead of React.

Benefits:

Visual drag-and-drop block editing (clients love this)
No React/JavaScript required (developers save time)
ACF's familiar field builder
Clean data storage like traditional ACF
Faster development than pure Gutenberg

Cost:

ACF Pro: £38/year per site (or £200/year unlimited)
Development time: 3-5 hours per block (vs 6-12 hours for pure Gutenberg)

This is my recommended approach for most custom WordPress sites. You get the best of both worlds.

Option 2: ACF for Structure + Gutenberg for Content

What it is: Use ACF Flexible Content for page structure (hero, features, testimonials), but allow Gutenberg within content areas.

Benefits:

Developers control important sections
Editors get freedom in content areas
Combines structured layouts with flexible content
Good balance of control and flexibility

When this works well:

Sites with repeating section patterns
Teams that want some Gutenberg experience
Projects needing both structure and freedom

Migration Considerations: The Real Costs

Switching is Expensive - Choose Wisely

Moving from ACF to Gutenberg:

Time required: 40-80 hours for typical business website Cost: £3,000-6,000 in development

What's involved:

Rebuild all flexible layouts as Gutenberg blocks
Migrate content data
Retrain content team
Extensive testing across all pages
Fix inevitable issues

When it makes sense:

Complete site rebuild anyway
Long-term WordPress alignment important
Team specifically wants Gutenberg
Budget allows significant development

Moving from Gutenberg to ACF

Time required: 30-60 hours for typical site Cost: £2,500-5,000 in development

What's involved:

Rebuild blocks as ACF layouts
Content data migration
Template rewrites
Team retraining
Thorough content verification

When it makes sense:

Performance is critical concern
Block maintenance costs too high
Need precise design control
Development team prefers PHP

The Honest Truth

Most migrations aren't worth it unless:

You're doing a complete rebuild anyway
Current system causing significant problems
Long-term cost savings justify upfront expense

Better approach: Choose wisely from the start based on your specific needs.

My Recommendation After 50+ WordPress Projects

After building numerous sites with both approaches, here's my honest guidance:

For Most Custom Business Websites: ACF Blocks (Hybrid)

My go-to approach for 80% of client projects:

ACF Pro with ACF Blocks combines the best of both worlds:

Clients love it: Visual drag-and-drop editing like Gutenberg
Developers love it: Faster development, no React required
Better performance: Cleaner code than pure Gutenberg
Lower maintenance: More stable than custom Gutenberg blocks
Reasonable cost: £38/year per site

Real client feedback:

"Much easier than our old WordPress setup. I can build pages myself without calling the developer every time." - Bristol consulting firm

Total cost over 5 years:

Initial development: £2,500-4,000
ACF Pro license: £190 (5 years)
Maintenance: £1,500-3,000
Total: £4,190-7,190

For Pure Content Sites: Gutenberg

When Gutenberg is the better choice:

If your site is primarily blog posts and articles with standard layouts:

Writers need visual editing
Standard content patterns work
No complex custom sections
Budget is tight (no ACF Pro cost)

Examples: News sites, personal blogs, simple company blogs

Total cost over 5 years:

Initial development: £3,000-5,000
No plugin costs
Maintenance: £4,000-7,500 (higher due to potential breaking changes)
Total: £7,000-12,500

For Complex Data Sites: Pure ACF Flexible Content

When traditional ACF makes more sense:

For data-heavy, complex sites where performance is critical:

E-commerce product pages
Directory listings
Review/comparison sites
Sites needing custom APIs

Benefit: Maximum control, best performance, easiest data queries

Tradeoff: Editors don't get visual preview (must view live site to see changes)

What I Actually Build

My project breakdown:

70% - ACF Blocks (hybrid approach)
20% - Pure ACF Flexible Content (complex/data-heavy sites)
10% - Gutenberg only (simple content sites or client preference)

Honest truth: For serious business websites, ACF Blocks delivers the best combination of editor experience, development efficiency, and long-term maintainability.

The Bottom Line: Which Should You Choose?

Both Gutenberg and ACF are powerful, but they solve different problems. Here's how to decide:

Quick Decision Framework

Choose ACF Blocks (my recommendation) if:

You're building a custom business website
Budget allows £2,500+ for development
You want both visual editing AND good performance
Long-term maintenance costs matter
You value design precision

Choose Gutenberg if:

Pure content/blog site
Very tight budget (under £2,000)
Standard layouts are fine
Team specifically wants Gutenberg experience
WordPress alignment is priority

Choose Pure ACF Flexible Content if:

Complex data-driven site
Performance is absolutely critical
Need maximum design control
Team prefers structured editing
Don't need visual page building

What Actually Matters

Don't choose based on:

❌ What's "newer" or "more modern"
❌ What you read WordPress is pushing
❌ What other developers say on forums

Choose based on:

✓ Your actual project requirements
✓ Your team's strengths
✓ Total cost over 5 years (not just initial build)
✓ Editor experience for YOUR team
✓ Performance needs for YOUR audience

Real-World Advice

After 50+ WordPress projects, here's what I've learned:

For serious business websites: ACF Blocks wins. You get visual editing clients love, development efficiency developers appreciate, and better long-term costs.

For simple content sites: Gutenberg is fine. Don't overcomplicate it.

For complex data sites: Pure ACF Flexible Content gives you the control you need.

Still WordPress at All?

Honest consideration: Before choosing between Gutenberg and ACF, ask if WordPress is even the right choice for your project.

For many custom sites in 2025, modern alternatives like Payload CMS offer better performance, cleaner development, and lower long-term costs.

But if WordPress makes sense for your situation, ACF Blocks is my go-to recommendation for most projects.

Need Help Deciding?

I've built custom WordPress sites with Gutenberg, ACF, and ACF Blocks. I can assess your specific project needs and recommend the approach that makes the most sense - not just technically, but strategically for your business goals.

Get in touch to discuss your project. I'll provide honest guidance on whether WordPress is right for you, and if so, which approach will deliver the best long-term value.