diff --git a/CHANGELOG.md b/CHANGELOG.md
index e40421238cc4..2b7eab50d4f9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Add support for prefixes ([#14501](https://github.com/tailwindlabs/tailwindcss/pull/14501))
 - Expose timing information in debug mode ([#14553](https://github.com/tailwindlabs/tailwindcss/pull/14553))
+- Add support for `blocklist` in config files ([#14556](https://github.com/tailwindlabs/tailwindcss/pull/14556))
 - _Experimental_: Add template codemods for migrating `bg-gradient-*` utilities to `bg-linear-*` ([#14537](https://github.com/tailwindlabs/tailwindcss/pull/14537]))
 - _Experimental_: Migrate `@import "tailwindcss/tailwind.css"` to `@import "tailwindcss"` ([#14514](https://github.com/tailwindlabs/tailwindcss/pull/14514))
 
diff --git a/packages/tailwindcss/src/compat/apply-compat-hooks.ts b/packages/tailwindcss/src/compat/apply-compat-hooks.ts
index 1cf3cc8102ff..915cfea427db 100644
--- a/packages/tailwindcss/src/compat/apply-compat-hooks.ts
+++ b/packages/tailwindcss/src/compat/apply-compat-hooks.ts
@@ -229,6 +229,10 @@ export async function applyCompatibilityHooks({
     designSystem.theme.prefix = resolvedConfig.prefix
   }
 
+  for (let candidate of resolvedConfig.blocklist) {
+    designSystem.invalidCandidates.add(candidate)
+  }
+
   // Replace `resolveThemeValue` with a version that is backwards compatible
   // with dot-notation but also aware of any JS theme configurations registered
   // by plugins or JS config files. This is significantly slower than just
diff --git a/packages/tailwindcss/src/compat/config.test.ts b/packages/tailwindcss/src/compat/config.test.ts
index 4725a8f2dd4b..bb25a02317d5 100644
--- a/packages/tailwindcss/src/compat/config.test.ts
+++ b/packages/tailwindcss/src/compat/config.test.ts
@@ -1371,3 +1371,72 @@ test('a prefix must be letters only', async () => {
     `[Error: The prefix "__" is invalid. Prefixes must be lowercase ASCII letters (a-z) only.]`,
   )
 })
+
+test('blocklisted canddiates are not generated', async () => {
+  let compiler = await compile(
+    css`
+      @theme reference {
+        --color-white: #fff;
+        --breakpoint-md: 48rem;
+      }
+      @tailwind utilities;
+      @config "./config.js";
+    `,
+    {
+      async loadModule(id, base) {
+        return {
+          base,
+          module: {
+            blocklist: ['bg-white'],
+          },
+        }
+      },
+    },
+  )
+
+  // bg-white will not get generated
+  expect(compiler.build(['bg-white'])).toEqual('')
+
+  // underline will as will md:bg-white
+  expect(compiler.build(['underline', 'bg-white', 'md:bg-white'])).toMatchInlineSnapshot(`
+    ".underline {
+      text-decoration-line: underline;
+    }
+    .md\\:bg-white {
+      @media (width >= 48rem) {
+        background-color: var(--color-white, #fff);
+      }
+    }
+    "
+  `)
+})
+
+test('blocklisted canddiates cannot be used with `@apply`', async () => {
+  await expect(() =>
+    compile(
+      css`
+        @theme reference {
+          --color-white: #fff;
+          --breakpoint-md: 48rem;
+        }
+        @tailwind utilities;
+        @config "./config.js";
+        .foo {
+          @apply bg-white;
+        }
+      `,
+      {
+        async loadModule(id, base) {
+          return {
+            base,
+            module: {
+              blocklist: ['bg-white'],
+            },
+          }
+        },
+      },
+    ),
+  ).rejects.toThrowErrorMatchingInlineSnapshot(
+    `[Error: Cannot apply unknown utility class: bg-white]`,
+  )
+})
diff --git a/packages/tailwindcss/src/compat/config/resolve-config.ts b/packages/tailwindcss/src/compat/config/resolve-config.ts
index 0c20bf7c335c..acf89c3cf024 100644
--- a/packages/tailwindcss/src/compat/config/resolve-config.ts
+++ b/packages/tailwindcss/src/compat/config/resolve-config.ts
@@ -27,6 +27,7 @@ interface ResolutionContext {
 }
 
 let minimal: ResolvedConfig = {
+  blocklist: [],
   prefix: '',
   darkMode: null,
   theme: {},
@@ -64,6 +65,10 @@ export function resolveConfig(design: DesignSystem, files: ConfigFile[]): Resolv
     if ('prefix' in config && config.prefix !== undefined) {
       ctx.result.prefix = config.prefix ?? ''
     }
+
+    if ('blocklist' in config && config.blocklist !== undefined) {
+      ctx.result.blocklist = config.blocklist ?? []
+    }
   }
 
   // Merge themes
diff --git a/packages/tailwindcss/src/compat/config/types.ts b/packages/tailwindcss/src/compat/config/types.ts
index 4b6e072b58d2..289e1bae0cfd 100644
--- a/packages/tailwindcss/src/compat/config/types.ts
+++ b/packages/tailwindcss/src/compat/config/types.ts
@@ -78,3 +78,12 @@ export interface UserConfig {
 export interface ResolvedConfig {
   prefix: string
 }
+
+// `blocklist` support
+export interface UserConfig {
+  blocklist?: string[]
+}
+
+export interface ResolvedConfig {
+  blocklist: string[]
+}
diff --git a/packages/tailwindcss/src/compile.ts b/packages/tailwindcss/src/compile.ts
index 9b7b3ce468b0..c5de56c4c64a 100644
--- a/packages/tailwindcss/src/compile.ts
+++ b/packages/tailwindcss/src/compile.ts
@@ -22,6 +22,11 @@ export function compileCandidates(
 
   // Parse candidates and variants
   for (let rawCandidate of rawCandidates) {
+    if (designSystem.invalidCandidates.has(rawCandidate)) {
+      onInvalidCandidate?.(rawCandidate)
+      continue // Bail, invalid candidate
+    }
+
     let candidates = designSystem.parseCandidate(rawCandidate)
     if (candidates.length === 0) {
       onInvalidCandidate?.(rawCandidate)
diff --git a/packages/tailwindcss/src/design-system.ts b/packages/tailwindcss/src/design-system.ts
index 0bac8102d7de..e2b07a24b117 100644
--- a/packages/tailwindcss/src/design-system.ts
+++ b/packages/tailwindcss/src/design-system.ts
@@ -13,6 +13,8 @@ export type DesignSystem = {
   utilities: Utilities
   variants: Variants
 
+  invalidCandidates: Set<string>
+
   getClassOrder(classes: string[]): [string, bigint | null][]
   getClassList(): ClassEntry[]
   getVariants(): VariantEntry[]
@@ -45,12 +47,21 @@ export function buildDesignSystem(theme: Theme): DesignSystem {
     utilities,
     variants,
 
+    invalidCandidates: new Set(),
+
     candidatesToCss(classes: string[]) {
       let result: (string | null)[] = []
 
       for (let className of classes) {
-        let { astNodes } = compileCandidates([className], this)
-        if (astNodes.length === 0) {
+        let wasInvalid = false
+
+        let { astNodes } = compileCandidates([className], this, {
+          onInvalidCandidate(candidate) {
+            wasInvalid = true
+          },
+        })
+
+        if (astNodes.length === 0 || wasInvalid) {
           result.push(null)
         } else {
           result.push(toCss(astNodes))
diff --git a/packages/tailwindcss/src/index.ts b/packages/tailwindcss/src/index.ts
index ff74f1881aa1..82c8203a5522 100644
--- a/packages/tailwindcss/src/index.ts
+++ b/packages/tailwindcss/src/index.ts
@@ -399,9 +399,8 @@ export async function compile(
   }
 
   // Track all invalid candidates
-  let invalidCandidates = new Set<string>()
   function onInvalidCandidate(candidate: string) {
-    invalidCandidates.add(candidate)
+    designSystem.invalidCandidates.add(candidate)
   }
 
   // Track all valid candidates, these are the incoming `rawCandidate` that
@@ -419,7 +418,7 @@ export async function compile(
       // Add all new candidates unless we know that they are invalid.
       let prevSize = allValidCandidates.size
       for (let candidate of newRawCandidates) {
-        if (!invalidCandidates.has(candidate)) {
+        if (!designSystem.invalidCandidates.has(candidate)) {
           allValidCandidates.add(candidate)
           didChange ||= allValidCandidates.size !== prevSize
         }
diff --git a/packages/tailwindcss/src/intellisense.test.ts b/packages/tailwindcss/src/intellisense.test.ts
index 0eb4d16cc94f..f6a906c28e96 100644
--- a/packages/tailwindcss/src/intellisense.test.ts
+++ b/packages/tailwindcss/src/intellisense.test.ts
@@ -83,3 +83,24 @@ test('The variant `has-force` does not crash', () => {
 
   expect(has.selectors({ value: 'force' })).toMatchInlineSnapshot(`[]`)
 })
+
+test('Can produce CSS per candidate using `candidatesToCss`', () => {
+  let design = loadDesignSystem()
+  design.invalidCandidates = new Set(['bg-[#fff]'])
+
+  expect(design.candidatesToCss(['underline', 'i-dont-exist', 'bg-[#fff]', 'bg-[#000]']))
+    .toMatchInlineSnapshot(`
+    [
+      ".underline {
+      text-decoration-line: underline;
+    }
+    ",
+      null,
+      null,
+      ".bg-\\[\\#000\\] {
+      background-color: #000;
+    }
+    ",
+    ]
+  `)
+})