diff --git a/packages/server/src/api/rest/index.ts b/packages/server/src/api/rest/index.ts
index a9a39a42..6ea0943b 100644
--- a/packages/server/src/api/rest/index.ts
+++ b/packages/server/src/api/rest/index.ts
@@ -45,6 +45,12 @@ export type Options = {
      * Defaults to '_'.
      */
     idDivider?: string;
+
+    /**
+     * The charset used for URL segment values. Defaults to `a-zA-Z0-9-_~ %`.
+     * If the idDivider is set to a different value, it should be included in the charset.
+     */
+    urlSegmentNameCharset?: string;
 };
 
 type RelationshipInfo = {
@@ -202,18 +208,21 @@ class RequestHandler extends APIHandlerBase {
 
     // all known types and their metadata
     private typeMap: Record<string, ModelInfo>;
-    public idDivider;
+
+    // divider used to separate compound ID fields
+    private idDivider;
 
     private urlPatterns;
 
     constructor(private readonly options: Options) {
         super();
         this.idDivider = options.idDivider ?? '_';
-        this.urlPatterns = this.buildUrlPatterns(this.idDivider);
+        const segmentCharset = options.urlSegmentNameCharset ?? 'a-zA-Z0-9-_~ %';
+        this.urlPatterns = this.buildUrlPatterns(this.idDivider, segmentCharset);
     }
 
-    buildUrlPatterns(idDivider: string) {
-        const options = { segmentValueCharset: `a-zA-Z0-9-_~ %${idDivider}` };
+    buildUrlPatterns(idDivider: string, urlSegmentNameCharset: string) {
+        const options = { segmentValueCharset: urlSegmentNameCharset };
         return {
             // collection operations
             collection: new UrlPattern('/:type', options),
diff --git a/packages/server/tests/api/rest.test.ts b/packages/server/tests/api/rest.test.ts
index 6c449676..d37c5d9b 100644
--- a/packages/server/tests/api/rest.test.ts
+++ b/packages/server/tests/api/rest.test.ts
@@ -2549,7 +2549,12 @@ describe('REST server tests', () => {
             zodSchemas = params.zodSchemas;
             modelMeta = params.modelMeta;
 
-            const _handler = makeHandler({ endpoint: 'http://localhost/api', pageSize: 5, idDivider });
+            const _handler = makeHandler({
+                endpoint: 'http://localhost/api',
+                pageSize: 5,
+                idDivider,
+                urlSegmentNameCharset: 'a-zA-Z0-9-_~ %@.',
+            });
             handler = (args) =>
                 _handler({ ...args, zodSchemas, modelMeta, url: new URL(`http://localhost/${args.path}`) });
         });