diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
index 00d1bf70..fc3456ec 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBloodPressureProfile.ts
@@ -46,7 +46,7 @@ import {
 
 export type USCoreBloodPressureProfileRaw = {
     status: ("registered" | "preliminary" | "final" | "amended" | "corrected" | "cancelled" | "entered-in-error" | "unknown");
-    subject: Reference<"Patient">;
+    subject: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>;
     category?: CodeableConcept<("social-history" | "vital-signs" | "imaging" | "laboratory" | "procedure" | "survey" | "exam" | "therapy" | "activity" | string)>[];
     component?: ObservationComponent[];
 }
@@ -145,11 +145,11 @@ export class USCoreBloodPressureProfile {
         return this;
     }
 
-    getSubject () : Reference<"Patient"> | undefined {
-        return this.resource.subject as Reference<"Patient"> | undefined;
+    getSubject () : Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined {
+        return this.resource.subject as Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined;
     }
 
-    setSubject (value: Reference<"Patient">) : this {
+    setSubject (value: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>) : this {
         Object.assign(this.resource, { subject: value });
         return this;
     }
diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
index 781a0f11..f5a33542 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreBodyWeightProfile.ts
@@ -38,7 +38,7 @@ import {
 
 export type USCoreBodyWeightProfileRaw = {
     status: ("registered" | "preliminary" | "final" | "amended" | "corrected" | "cancelled" | "entered-in-error" | "unknown");
-    subject: Reference<"Patient">;
+    subject: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>;
     category?: CodeableConcept<("social-history" | "vital-signs" | "imaging" | "laboratory" | "procedure" | "survey" | "exam" | "therapy" | "activity" | string)>[];
 }
 
@@ -119,11 +119,11 @@ export class USCoreBodyWeightProfile {
         return this;
     }
 
-    getSubject () : Reference<"Patient"> | undefined {
-        return this.resource.subject as Reference<"Patient"> | undefined;
+    getSubject () : Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined {
+        return this.resource.subject as Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined;
     }
 
-    setSubject (value: Reference<"Patient">) : this {
+    setSubject (value: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>) : this {
         Object.assign(this.resource, { subject: value });
         return this;
     }
diff --git a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
index 2ce509e3..7ed3d3df 100644
--- a/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
+++ b/examples/typescript-r4-us-core/fhir-types/hl7-fhir-us-core/profiles/Observation_USCoreVitalSignsProfile.ts
@@ -38,7 +38,7 @@ import {
 export type USCoreVitalSignsProfileRaw = {
     status: ("registered" | "preliminary" | "final" | "amended" | "corrected" | "cancelled" | "entered-in-error" | "unknown");
     code: CodeableConcept<("2708-6" | "29463-7" | "3140-1" | "3150-0" | "3151-8" | "39156-5" | "59408-5" | "59575-1" | "59576-9" | "77606-2" | "8287-5" | "8289-1" | "8302-2" | "8306-3" | "8310-5" | "8462-4" | "8478-0" | "8480-6" | "8867-4" | "9279-1" | "9843-4" | string)>;
-    subject: Reference<"Patient">;
+    subject: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>;
     category?: CodeableConcept<("social-history" | "vital-signs" | "imaging" | "laboratory" | "procedure" | "survey" | "exam" | "therapy" | "activity" | string)>[];
 }
 
@@ -127,11 +127,11 @@ export class USCoreVitalSignsProfile {
         return this;
     }
 
-    getSubject () : Reference<"Patient"> | undefined {
-        return this.resource.subject as Reference<"Patient"> | undefined;
+    getSubject () : Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined {
+        return this.resource.subject as Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined;
     }
 
-    setSubject (value: Reference<"Patient">) : this {
+    setSubject (value: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>) : this {
         Object.assign(this.resource, { subject: value });
         return this;
     }
diff --git a/src/api/writer-generator/typescript/utils.ts b/src/api/writer-generator/typescript/utils.ts
index fc9ab91a..3e8d9679 100644
--- a/src/api/writer-generator/typescript/utils.ts
+++ b/src/api/writer-generator/typescript/utils.ts
@@ -80,9 +80,23 @@ export const resolveFieldTsType = (
         return tsEnumType(field.enum);
     }
     if (field.reference && field.reference.resource.length > 0) {
-        const resolved = field.reference.resource.map((ref) => (resolveRef ? resolveRef(ref) : ref));
-        const references = resolved
-            .map((ref) => (isFamilyType?.(ref) ? `string /* ${ref.name} */` : `"${ref.name}"`))
+        // Profile targets are replaced by their base resource type; keep the
+        // profile URLs as comments to make server-side validation errors traceable.
+        const profilesByResource: Record<string, string[]> = {};
+        if (resolveRef) {
+            for (const profile of field.reference.profiles ?? []) {
+                const base = resolveRef(profile).name;
+                (profilesByResource[base] ??= []).push(profile.url);
+            }
+        }
+        const references = field.reference.resource
+            .map((original) => {
+                const ref = resolveRef ? resolveRef(original) : original;
+                if (isFamilyType?.(ref)) return `string /* ${ref.name} */`;
+                const profiles = profilesByResource[ref.name];
+                if (profiles) return `"${ref.name}" /* ${profiles.join(", ")} */`;
+                return `"${ref.name}"`;
+            })
             .join(" | ");
         return `Reference<${references}>`;
     }
diff --git a/test/api/write-generator/__snapshots__/typescript.test.ts.snap b/test/api/write-generator/__snapshots__/typescript.test.ts.snap
index c6bc1688..ea68c285 100644
--- a/test/api/write-generator/__snapshots__/typescript.test.ts.snap
+++ b/test/api/write-generator/__snapshots__/typescript.test.ts.snap
@@ -1364,7 +1364,7 @@ import {
 
 export type USCoreBloodPressureProfileRaw = {
     status: ("registered" | "preliminary" | "final" | "amended" | "corrected" | "cancelled" | "entered-in-error" | "unknown");
-    subject: Reference<"Patient">;
+    subject: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>;
     category?: CodeableConcept<("social-history" | "vital-signs" | "imaging" | "laboratory" | "procedure" | "survey" | "exam" | "therapy" | "activity" | string)>[];
     component?: ObservationComponent[];
 }
@@ -1463,11 +1463,11 @@ export class USCoreBloodPressureProfile {
         return this;
     }
 
-    getSubject () : Reference<"Patient"> | undefined {
-        return this.resource.subject as Reference<"Patient"> | undefined;
+    getSubject () : Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined {
+        return this.resource.subject as Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined;
     }
 
-    setSubject (value: Reference<"Patient">) : this {
+    setSubject (value: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>) : this {
         Object.assign(this.resource, { subject: value });
         return this;
     }
@@ -1793,7 +1793,7 @@ import {
 
 export type USCoreBodyWeightProfileRaw = {
     status: ("registered" | "preliminary" | "final" | "amended" | "corrected" | "cancelled" | "entered-in-error" | "unknown");
-    subject: Reference<"Patient">;
+    subject: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>;
     category?: CodeableConcept<("social-history" | "vital-signs" | "imaging" | "laboratory" | "procedure" | "survey" | "exam" | "therapy" | "activity" | string)>[];
 }
 
@@ -1874,11 +1874,11 @@ export class USCoreBodyWeightProfile {
         return this;
     }
 
-    getSubject () : Reference<"Patient"> | undefined {
-        return this.resource.subject as Reference<"Patient"> | undefined;
+    getSubject () : Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined {
+        return this.resource.subject as Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */> | undefined;
     }
 
-    setSubject (value: Reference<"Patient">) : this {
+    setSubject (value: Reference<"Patient" /* http://hl7.org/fhir/us/core/StructureDefinition/us-core-patient */>) : this {
         Object.assign(this.resource, { subject: value });
         return this;
     }
diff --git a/test/unit/api/writer-generator/typescript/utils.test.ts b/test/unit/api/writer-generator/typescript/utils.test.ts
new file mode 100644
index 00000000..3603bae1
--- /dev/null
+++ b/test/unit/api/writer-generator/typescript/utils.test.ts
@@ -0,0 +1,49 @@
+import { describe, expect, test } from "bun:test";
+import { fieldTsType } from "@root/api/writer-generator/typescript/utils";
+import type { CanonicalUrl, Name, ProfileIdentifier, RegularField, TypeIdentifier } from "@root/typeschema/types";
+
+const makeIdentifier = (kind: TypeIdentifier["kind"], name: string): TypeIdentifier => ({
+    kind,
+    package: "test-package",
+    version: "1.0.0",
+    name: name as Name,
+    url: `http://example.org/StructureDefinition/${name}` as CanonicalUrl,
+});
+
+const referenceType = makeIdentifier("complex-type", "Reference");
+const patient = makeIdentifier("resource", "Patient");
+const group = makeIdentifier("resource", "Group");
+const usCorePatient = makeIdentifier("profile", "USCorePatient") as ProfileIdentifier;
+const testPatient = makeIdentifier("profile", "TestPatient") as ProfileIdentifier;
+
+const resolveRef = (ref: TypeIdentifier): TypeIdentifier => {
+    if (ref.name === usCorePatient.name || ref.name === testPatient.name) return patient;
+    return ref;
+};
+
+describe("fieldTsType reference targets", () => {
+    test("plain resource targets have no comment", () => {
+        const field: RegularField = { type: referenceType, reference: { resource: [patient, group] } };
+        expect(fieldTsType(field, resolveRef)).toBe(`Reference<"Patient" | "Group">`);
+    });
+
+    test("profile target replaced by its resource type keeps the profile url as a comment", () => {
+        const field: RegularField = {
+            type: referenceType,
+            reference: { resource: [patient], profiles: [usCorePatient] },
+        };
+        expect(fieldTsType(field, resolveRef)).toBe(
+            `Reference<"Patient" /* http://example.org/StructureDefinition/USCorePatient */>`,
+        );
+    });
+
+    test("multiple profiles of the same resource are listed in one comma-separated comment", () => {
+        const field: RegularField = {
+            type: referenceType,
+            reference: { resource: [group, patient], profiles: [usCorePatient, testPatient] },
+        };
+        expect(fieldTsType(field, resolveRef)).toBe(
+            `Reference<"Group" | "Patient" /* http://example.org/StructureDefinition/USCorePatient, http://example.org/StructureDefinition/TestPatient */>`,
+        );
+    });
+});