diff --git a/packages/build/src/plugins/node_version.ts b/packages/build/src/plugins/node_version.ts
index 3a1b0224c4..0de069a201 100644
--- a/packages/build/src/plugins/node_version.ts
+++ b/packages/build/src/plugins/node_version.ts
@@ -1,9 +1,11 @@
+import { dirname } from 'path'
 import { execPath, version as currentVersion } from 'process'
 
 import semver from 'semver'
 import link from 'terminal-link'
 
 import { logWarning, logWarningSubHeader } from '../log/logger.js'
+import { getPackageJson } from '../utils/package.js'
 
 export type PluginsLoadedFrom = 'auto_install' | 'local' | 'package.json'
 
@@ -22,6 +24,7 @@ export type PluginsOptions = {
  * If the users preferred Node.js version is below that we have to fall back to the system node version
  */
 const MINIMUM_REQUIRED_NODE_VERSION = '>=18.14.0'
+const UPCOMING_MINIMUM_REQUIRED_NODE_VERSION = '>=22.12.0'
 
 /**
  * Local plugins and `package.json`-installed plugins use user's preferred Node.js version if higher than our minimum
@@ -30,28 +33,39 @@ const MINIMUM_REQUIRED_NODE_VERSION = '>=18.14.0'
  * usually the system's Node.js version.
  * If the user Node version does not satisfy our supported engine range use our own system Node version
  */
-export const addPluginsNodeVersion = function ({ pluginsOptions, nodePath, userNodeVersion, logs }) {
+export const addPluginsNodeVersion = function ({
+  featureFlags,
+  pluginsOptions,
+  nodePath,
+  userNodeVersion,
+  logs,
+  systemLog,
+}) {
   const currentNodeVersion = semver.clean(currentVersion)
   return Promise.all(
     pluginsOptions.map((pluginOptions) =>
       addPluginNodeVersion({
+        featureFlags,
         pluginOptions,
         currentNodeVersion,
         userNodeVersion,
         nodePath,
         logs,
+        systemLog,
       }),
     ),
   )
 }
 
 const addPluginNodeVersion = async function ({
+  featureFlags,
   pluginOptions,
-  pluginOptions: { loadedFrom, packageName },
+  pluginOptions: { loadedFrom, packageName, pluginPath },
   currentNodeVersion,
   userNodeVersion,
   nodePath,
   logs,
+  systemLog,
 }: {
   pluginOptions: PluginsOptions
   [key: string]: any
@@ -66,6 +80,58 @@ const addPluginNodeVersion = async function ({
     return systemNode
   }
 
+  if (
+    featureFlags.build_warn_upcoming_system_version_change &&
+    !semver.satisfies(userNodeVersion, UPCOMING_MINIMUM_REQUIRED_NODE_VERSION)
+  ) {
+    logWarningSubHeader(
+      logs,
+      `Warning: Starting June 16, 2026 plugin "${packageName}" will be executed with Node.js version 22.`,
+    )
+    logWarning(
+      logs,
+      `  We're upgrading our system Node.js minimum on that day, which means the plugin cannot be executed with your defined Node.js version ${userNodeVersion}.
+
+  Please make sure your plugin supports being run on Node.js 22.
+
+  Read more about our minimum required version in our ${link(
+    'forums announcement',
+    'https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-18-node-js-20/162662',
+  )}`,
+    )
+
+    if (pluginPath) {
+      const pluginDir = dirname(pluginPath)
+      const { packageJson: pluginPackageJson, packageDir } = await getPackageJson(pluginDir)
+
+      // `getPackageJson` walks up to the nearest `package.json`. For a `package.json`-installed
+      // plugin that's the plugin's own manifest, but for a local single-file plugin
+      // (e.g. `./plugins/foo.js`) it resolves an ancestor — typically the *site's*
+      // `package.json`, whose `engines.node` describes the site rather than the plugin. Only
+      // trust the resolved range when the manifest belongs to the plugin: an installed package,
+      // or a local plugin shipping its own `package.json` alongside its entry file.
+      const pluginOwnsPackageJson = loadedFrom === 'package.json' || packageDir === pluginDir
+      const pluginNodeVersionRange = pluginOwnsPackageJson ? pluginPackageJson.engines?.node : undefined
+
+      // Ensure Node.js version is compatible with plugin's `engines.node`
+      if (!pluginOwnsPackageJson) {
+        systemLog(`plugin "${packageName}" node support range could not be determined (no own package.json)`)
+      } else if (!pluginNodeVersionRange) {
+        systemLog(`plugin "${packageName}" does not specify node support range`)
+      } else if (semver.satisfies('22.12.0', pluginNodeVersionRange)) {
+        systemLog(`plugin "${packageName}" node support range includes v22`)
+      } else {
+        logWarning(
+          logs,
+          `  In its package.json, the plugin "${packageName}" declares a Node.js version range ("${pluginNodeVersionRange}") that does not include Node.js 22. Please upgrade the plugin so it can be run on Node.js 22.`,
+        )
+        systemLog(`plugin "${packageName}" node support range does NOT include v22`)
+      }
+    } else {
+      systemLog(`plugin "${packageName}" pluginPath not available`)
+    }
+  }
+
   if (semver.satisfies(userNodeVersion, MINIMUM_REQUIRED_NODE_VERSION)) {
     return userNode
   }
@@ -77,7 +143,7 @@ const addPluginNodeVersion = async function ({
 
   Read more about our minimum required version in our ${link(
     'forums announcement',
-    'https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-14-node-js-16/136405',
+    'https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-18-node-js-20/162662',
   )}`,
   )
 
diff --git a/packages/build/src/plugins/resolve.js b/packages/build/src/plugins/resolve.js
index 08284ec5b9..23b3e7f6a9 100644
--- a/packages/build/src/plugins/resolve.js
+++ b/packages/build/src/plugins/resolve.js
@@ -40,10 +40,12 @@ export const resolvePluginsPath = async function ({
     pluginsOptions.map((pluginOptions) => resolvePluginPath({ pluginOptions, buildDir, packagePath, autoPluginsDir })),
   )
   const pluginsOptionsB = await addPluginsNodeVersion({
+    featureFlags,
     pluginsOptions: pluginsOptionsA,
     nodePath,
     userNodeVersion,
     logs,
+    systemLog,
   })
 
   const pluginsOptionsC = await addPinnedVersions({ pluginsOptions: pluginsOptionsB, api, siteInfo, sendStatus })
diff --git a/packages/build/tests/core/snapshots/tests.js.md b/packages/build/tests/core/snapshots/tests.js.md
index 4efaa19f44..34b344a9cc 100644
--- a/packages/build/tests/core/snapshots/tests.js.md
+++ b/packages/build/tests/core/snapshots/tests.js.md
@@ -1173,7 +1173,7 @@ Generated by [AVA](https://avajs.dev).
     > Warning: ./plugin.js will be executed with Node.js version 1.0.0␊
       The plugin cannot be executed with your defined Node.js version 1.0.0␊
     ␊
-      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-14-node-js-16/136405)␊
+      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-18-node-js-20/162662)␊
     ␊
     > Loading plugins␊
        - ./plugin.js@1.0.0 from netlify.toml␊
@@ -1232,7 +1232,7 @@ Generated by [AVA](https://avajs.dev).
     > Warning: netlify-plugin-test will be executed with Node.js version 1.0.0␊
       The plugin cannot be executed with your defined Node.js version 1.0.0␊
     ␊
-      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-14-node-js-16/136405)␊
+      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-18-node-js-20/162662)␊
     ␊
     > Loading plugins␊
        - netlify-plugin-test@1.0.0 from netlify.toml and package.json␊
diff --git a/packages/build/tests/core/snapshots/tests.js.snap b/packages/build/tests/core/snapshots/tests.js.snap
index 47bd11481a..edab53a293 100644
Binary files a/packages/build/tests/core/snapshots/tests.js.snap and b/packages/build/tests/core/snapshots/tests.js.snap differ
diff --git a/packages/build/tests/plugins/fixtures/engines_no_package/netlify.toml b/packages/build/tests/plugins/fixtures/engines_no_package/netlify.toml
new file mode 100644
index 0000000000..13115b066d
--- /dev/null
+++ b/packages/build/tests/plugins/fixtures/engines_no_package/netlify.toml
@@ -0,0 +1,2 @@
+[[plugins]]
+package = "./plugins/plugin.js"
diff --git a/packages/build/tests/plugins/fixtures/engines_no_package/package.json b/packages/build/tests/plugins/fixtures/engines_no_package/package.json
new file mode 100644
index 0000000000..8aa0c5ab3f
--- /dev/null
+++ b/packages/build/tests/plugins/fixtures/engines_no_package/package.json
@@ -0,0 +1,11 @@
+{
+  "name": "test",
+  "version": "0.0.1",
+  "type": "module",
+  "description": "test",
+  "license": "MIT",
+  "repository": "test",
+  "engines": {
+    "node": ">=99.0.0"
+  }
+}
diff --git a/packages/build/tests/plugins/fixtures/engines_no_package/plugins/manifest.yml b/packages/build/tests/plugins/fixtures/engines_no_package/plugins/manifest.yml
new file mode 100644
index 0000000000..a3512f0259
--- /dev/null
+++ b/packages/build/tests/plugins/fixtures/engines_no_package/plugins/manifest.yml
@@ -0,0 +1,2 @@
+name: test
+inputs: []
diff --git a/packages/build/tests/plugins/fixtures/engines_no_package/plugins/plugin.js b/packages/build/tests/plugins/fixtures/engines_no_package/plugins/plugin.js
new file mode 100644
index 0000000000..0603db7376
--- /dev/null
+++ b/packages/build/tests/plugins/fixtures/engines_no_package/plugins/plugin.js
@@ -0,0 +1 @@
+export const onPreBuild = function () {}
diff --git a/packages/build/tests/plugins/snapshots/tests.js.md b/packages/build/tests/plugins/snapshots/tests.js.md
index 619c75abab..654cfe0097 100644
--- a/packages/build/tests/plugins/snapshots/tests.js.md
+++ b/packages/build/tests/plugins/snapshots/tests.js.md
@@ -870,7 +870,7 @@ Generated by [AVA](https://avajs.dev).
     > Warning: ./plugin.js will be executed with Node.js version 1.0.0␊
       The plugin cannot be executed with your defined Node.js version 1.0.0␊
     ␊
-      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-14-node-js-16/136405)␊
+      Read more about our minimum required version in our forums announcement (https://answers.netlify.com/t/build-plugins-end-of-support-for-node-js-18-node-js-20/162662)␊
     ␊
     > Loading plugins␊
        - ./plugin.js@1.0.0 from netlify.toml␊
diff --git a/packages/build/tests/plugins/snapshots/tests.js.snap b/packages/build/tests/plugins/snapshots/tests.js.snap
index d950f076dc..fbb2693e44 100644
Binary files a/packages/build/tests/plugins/snapshots/tests.js.snap and b/packages/build/tests/plugins/snapshots/tests.js.snap differ
diff --git a/packages/build/tests/plugins/tests.js b/packages/build/tests/plugins/tests.js
index 2a2285f4bd..9520e8b567 100644
--- a/packages/build/tests/plugins/tests.js
+++ b/packages/build/tests/plugins/tests.js
@@ -111,14 +111,64 @@ test('Validate --node-path unsupported version does not fail when no plugins are
 })
 
 test('Validate --node-path version is supported by the plugin', async (t) => {
-  const nodePath = getNodePath('16.14.0')
-  const output = await new Fixture('./fixtures/engines')
-    .withFlags({
-      nodePath,
-      debug: false,
-    })
-    .runWithBuild()
-  t.true(normalizeOutput(output).includes('The Node.js version is 1.0.0 but the plugin "./plugin.js" requires >=1.0.0'))
+  const systemLog = await tmp.file()
+
+  try {
+    const nodePath = getNodePath('16.14.0')
+    const output = await new Fixture('./fixtures/engines')
+      .withFlags({
+        nodePath,
+        featureFlags: { build_warn_upcoming_system_version_change: true },
+        systemLogFile: systemLog.fd,
+        debug: false,
+      })
+      .runWithBuild()
+    t.true(
+      normalizeOutput(output).includes('The Node.js version is 1.0.0 but the plugin "./plugin.js" requires >=1.0.0'),
+    )
+    t.true(
+      output.includes('Warning: Starting June 16, 2026 plugin "./plugin.js" will be executed with Node.js version 22.'),
+    )
+    t.true(
+      output.includes(
+        'the plugin "./plugin.js" declares a Node.js version range (">=99.0.0") that does not include Node.js 22',
+      ),
+    )
+    const systemLogContents = await fs.readFile(systemLog.path, 'utf8')
+    t.true(systemLogContents.includes('plugin "./plugin.js" node support range does NOT include v22'))
+  } finally {
+    await systemLog.cleanup()
+  }
+})
+
+test('Does not attribute the site package.json engines to a local single-file plugin', async (t) => {
+  const systemLog = await tmp.file()
+
+  try {
+    const nodePath = getNodePath('16.14.0')
+    const output = await new Fixture('./fixtures/engines_no_package')
+      .withFlags({
+        nodePath,
+        featureFlags: { build_warn_upcoming_system_version_change: true },
+        systemLogFile: systemLog.fd,
+        debug: false,
+      })
+      .runWithBuild()
+    // The general advance-notice warning still fires for any sub-v22 local plugin
+    t.true(
+      output.includes(
+        'Warning: Starting June 16, 2026 plugin "./plugins/plugin.js" will be executed with Node.js version 22.',
+      ),
+    )
+    // But the targeted "engines exclude v22" warning must NOT fire: the only package.json
+    // reachable by walking up is the site's, not the plugin's.
+    t.false(output.includes('declares a Node.js version range'))
+    const systemLogContents = await fs.readFile(systemLog.path, 'utf8')
+    t.true(systemLogContents.includes('node support range could not be determined (no own package.json)'))
+    t.false(systemLogContents.includes('node support range does NOT include v22'))
+  } finally {
+    await systemLog.cleanup()
+  }
 })
 
 test('Validate --node-path exists', async (t) => {