diff --git a/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts b/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
index 105731277c..738b965499 100644
--- a/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
+++ b/packages/compiler-cli/test/ngtsc/ngtsc_spec.ts
@@ -2179,6 +2179,23 @@ runInEachFileSystem(os => {
       expect(jsContents).not.toContain(':Some text');
     });
 
+    it('should also render legacy id for ICUs when normal messages are using legacy ids', () => {
+      env.tsconfig({i18nInFormat: 'xliff'});
+      env.write(`test.ts`, `
+     import {Component} from '@angular/core';
+     @Component({
+       selector: 'test',
+       template: '<div i18n="@@custom">Some text {age, plural, 10 {ten} other {other}}</div>'
+     })
+     class FooCmp {}`);
+      env.driveMain();
+      const jsContents = env.getContents('test.js');
+      expect(jsContents)
+          .toContain(
+              ':@@720ba589d043a0497ac721ff972f41db0c919efb:{VAR_PLURAL, plural, 10 {ten} other {other}}');
+      expect(jsContents).toContain(':@@custom:Some text');
+    });
+
     it('@Component\'s `interpolation` should override default interpolation config', () => {
       env.write(`test.ts`, `
       import {Component} from '@angular/core';
diff --git a/packages/compiler/src/i18n/i18n_ast.ts b/packages/compiler/src/i18n/i18n_ast.ts
index 6e41f09a79..0476214f41 100644
--- a/packages/compiler/src/i18n/i18n_ast.ts
+++ b/packages/compiler/src/i18n/i18n_ast.ts
@@ -93,6 +93,8 @@ export class Placeholder implements Node {
 }
 
 export class IcuPlaceholder implements Node {
+  /** Used to capture a message computed from a previous processing pass (see `setI18nRefs()`). */
+  previousMessage?: Message;
   constructor(public value: Icu, public name: string, public sourceSpan: ParseSourceSpan) {}
 
   visit(visitor: Visitor, context?: any): any { return visitor.visitIcuPlaceholder(this, context); }
diff --git a/packages/compiler/src/i18n/i18n_parser.ts b/packages/compiler/src/i18n/i18n_parser.ts
index 92da672346..f1be0895c8 100644
--- a/packages/compiler/src/i18n/i18n_parser.ts
+++ b/packages/compiler/src/i18n/i18n_parser.ts
@@ -21,8 +21,8 @@ const _expParser = new ExpressionParser(new ExpressionLexer());
 export type VisitNodeFn = (html: html.Node, i18n: i18n.Node) => i18n.Node;
 
 export interface I18nMessageFactory {
-  (nodes: html.Node[], meaning: string, description: string, customId: string,
-   visitNodeFn?: VisitNodeFn): i18n.Message;
+  (nodes: html.Node[], meaning: string|undefined, description: string|undefined,
+   customId: string|undefined, visitNodeFn?: VisitNodeFn): i18n.Message;
 }
 
 /**
@@ -54,7 +54,7 @@ class _I18nVisitor implements html.Visitor {
       private _interpolationConfig: InterpolationConfig) {}
 
   public toI18nMessage(
-      nodes: html.Node[], meaning: string, description: string, customId: string,
+      nodes: html.Node[], meaning = '', description = '', customId = '',
       visitNodeFn: VisitNodeFn|undefined): i18n.Message {
     const context: I18nMessageVisitorContext = {
       isIcu: nodes.length == 1 && nodes[0] instanceof html.Expansion,
diff --git a/packages/compiler/src/render3/view/i18n/meta.ts b/packages/compiler/src/render3/view/i18n/meta.ts
index 6e6b67cb0c..3fed00ce11 100644
--- a/packages/compiler/src/render3/view/i18n/meta.ts
+++ b/packages/compiler/src/render3/view/i18n/meta.ts
@@ -23,10 +23,20 @@ export type I18nMeta = {
   meaning?: string
 };
 
-function setI18nRefs(html: html.Node & {i18n?: i18n.I18nMeta}, i18n: i18n.Node): i18n.Node {
-  html.i18n = i18n;
-  return i18n;
-}
+
+const setI18nRefs: VisitNodeFn = (htmlNode, i18nNode) => {
+  if (htmlNode instanceof html.NodeWithI18n) {
+    if (i18nNode instanceof i18n.IcuPlaceholder && htmlNode.i18n instanceof i18n.Message) {
+      // This html node represents an ICU but this is a second processing pass, and the legacy id
+      // was computed in the previous pass and stored in the `i18n` property as a message.
+      // We are about to wipe out that property so capture the previous message to be reused when
+      // generating the message for this ICU later. See `_generateI18nMessage()`.
+      i18nNode.previousMessage = htmlNode.i18n;
+    }
+    htmlNode.i18n = i18nNode;
+  }
+  return i18nNode;
+};
 
 /**
  * This visitor walks over HTML parse tree and converts information stored in
@@ -44,28 +54,10 @@ export class I18nMetaVisitor implements html.Visitor {
   private _generateI18nMessage(
       nodes: html.Node[], meta: string|i18n.I18nMeta = '',
       visitNodeFn?: VisitNodeFn): i18n.Message {
-    const parsed: I18nMeta =
-        typeof meta === 'string' ? parseI18nMeta(meta) : metaFromI18nMessage(meta as i18n.Message);
-    const message = this._createI18nMessage(
-        nodes, parsed.meaning || '', parsed.description || '', parsed.customId || '', visitNodeFn);
-    if (!message.id) {
-      // generate (or restore) message id if not specified in template
-      message.id = typeof meta !== 'string' && (meta as i18n.Message).id || decimalDigest(message);
-    }
-
-    if (this.i18nLegacyMessageIdFormat === 'xlf' || this.i18nLegacyMessageIdFormat === 'xliff') {
-      message.legacyId = computeDigest(message);
-    } else if (
-        this.i18nLegacyMessageIdFormat === 'xlf2' || this.i18nLegacyMessageIdFormat === 'xliff2' ||
-        this.i18nLegacyMessageIdFormat === 'xmb') {
-      message.legacyId = computeDecimalDigest(message);
-    } else if (typeof meta !== 'string') {
-      // This occurs if we are doing the 2nd pass after whitespace removal
-      // In that case we want to reuse the legacy message generated in the 1st pass
-      // See `parseTemplate()` in `packages/compiler/src/render3/view/template.ts`
-      message.legacyId = (meta as i18n.Message).legacyId;
-    }
-
+    const {meaning, description, customId} = this._parseMetadata(meta);
+    const message = this._createI18nMessage(nodes, meaning, description, customId, visitNodeFn);
+    this._setMessageId(message, meta);
+    this._setLegacyId(message, meta);
     return message;
   }
 
@@ -141,6 +133,57 @@ export class I18nMetaVisitor implements html.Visitor {
   visitAttribute(attribute: html.Attribute): any { return attribute; }
   visitComment(comment: html.Comment): any { return comment; }
   visitExpansionCase(expansionCase: html.ExpansionCase): any { return expansionCase; }
+
+  /**
+   * Parse the general form `meta` passed into extract the explicit metadata needed to create a
+   * `Message`.
+   *
+   * There are three possibilities for the `meta` variable
+   * 1) a string from an `i18n` template attribute: parse it to extract the metadata values.
+   * 2) a `Message` from a previous processing pass: reuse the metadata values in the message.
+   * 4) other: ignore this and just process the message metadata as normal
+   *
+   * @param meta the bucket that holds information about the message
+   * @returns the parsed metadata.
+   */
+  private _parseMetadata(meta: string|i18n.I18nMeta): I18nMeta {
+    return typeof meta === 'string' ? parseI18nMeta(meta) :
+                                      meta instanceof i18n.Message ? metaFromI18nMessage(meta) : {};
+  }
+
+  /**
+   * Generate (or restore) message id if not specified already.
+   */
+  private _setMessageId(message: i18n.Message, meta: string|i18n.I18nMeta): void {
+    if (!message.id) {
+      message.id = meta instanceof i18n.Message && meta.id || decimalDigest(message);
+    }
+  }
+
+  /**
+   * Update the `message` with a `legacyId` if necessary.
+   *
+   * @param message the message whose legacy id should be set
+   * @param meta information about the message being processed
+   */
+  private _setLegacyId(message: i18n.Message, meta: string|i18n.I18nMeta): void {
+    if (this.i18nLegacyMessageIdFormat === 'xlf' || this.i18nLegacyMessageIdFormat === 'xliff') {
+      message.legacyId = computeDigest(message);
+    } else if (
+        this.i18nLegacyMessageIdFormat === 'xlf2' || this.i18nLegacyMessageIdFormat === 'xliff2' ||
+        this.i18nLegacyMessageIdFormat === 'xmb') {
+      message.legacyId = computeDecimalDigest(message);
+    } else if (typeof meta !== 'string') {
+      // This occurs if we are doing the 2nd pass after whitespace removal (see `parseTemplate()` in
+      // `packages/compiler/src/render3/view/template.ts`).
+      // In that case we want to reuse the legacy message generated in the 1st pass (see
+      // `setI18nRefs()`).
+      const previousMessage = meta instanceof i18n.Message ?
+          meta :
+          meta instanceof i18n.IcuPlaceholder ? meta.previousMessage : undefined;
+      message.legacyId = previousMessage && previousMessage.legacyId;
+    }
+  }
 }
 
 export function metaFromI18nMessage(message: i18n.Message, id: string | null = null): I18nMeta {
diff --git a/packages/compiler/test/render3/view/i18n_spec.ts b/packages/compiler/test/render3/view/i18n_spec.ts
index c69ad86693..b9b77c1ca3 100644
--- a/packages/compiler/test/render3/view/i18n_spec.ts
+++ b/packages/compiler/test/render3/view/i18n_spec.ts
@@ -21,7 +21,7 @@ import {formatI18nPlaceholderName} from '../../../src/render3/view/i18n/util';
 import {parseR3 as parse} from './util';
 
 const expressionParser = new Parser(new Lexer());
-const i18nOf = (element: t.Node & {i18n?: i18n.AST}) => element.i18n !;
+const i18nOf = (element: t.Node & {i18n?: i18n.I18nMeta}) => element.i18n !;
 
 describe('I18nContext', () => {
   it('should support i18n content collection', () => {