diff --git a/libs/transloco/src/lib/tests/service/translate.spec.ts b/libs/transloco/src/lib/tests/service/translate.spec.ts
index 88255352b..0c234f5b6 100644
--- a/libs/transloco/src/lib/tests/service/translate.spec.ts
+++ b/libs/transloco/src/lib/tests/service/translate.spec.ts
@@ -79,4 +79,16 @@ describe('translate', () => {
       'Admin Lazy spanish'
     );
   }));
+  
+  it('should return the translation when availableLangs is skipped', fakeAsync(() => {
+    service.setAvailableLangs(undefined);
+    loadLang(service);
+    expect(service.translate('home')).toEqual(mockLangs['en'].home);
+  }));
+  
+  it('should return the translation when availableLangs is set to null', fakeAsync(() => {
+    service.setAvailableLangs(null);
+    loadLang(service);
+    expect(service.translate('home')).toEqual(mockLangs['en'].home);
+  }));
 });
diff --git a/libs/transloco/src/lib/transloco.config.ts b/libs/transloco/src/lib/transloco.config.ts
index 35a803763..f5311b204 100644
--- a/libs/transloco/src/lib/transloco.config.ts
+++ b/libs/transloco/src/lib/transloco.config.ts
@@ -8,7 +8,7 @@ export interface TranslocoConfig {
   prodMode: boolean;
   fallbackLang?: string | string[];
   failedRetries: number;
-  availableLangs: AvailableLangs;
+  availableLangs?: AvailableLangs;
   flatten: {
     aot: boolean;
   };
diff --git a/libs/transloco/src/lib/transloco.service.ts b/libs/transloco/src/lib/transloco.service.ts
index 1e13e1d4d..9b8bc3edb 100644
--- a/libs/transloco/src/lib/transloco.service.ts
+++ b/libs/transloco/src/lib/transloco.service.ts
@@ -102,7 +102,7 @@ export class TranslocoService implements OnDestroy {
   private cache = new Map<string, Observable<Translation>>();
   private firstFallbackLang: string | undefined;
   private defaultLang = '';
-  private availableLangs: AvailableLangs = [];
+  private availableLangs?: AvailableLangs;
   private isResolvedMissingOnce = false;
   private lang: BehaviorSubject<string>;
   private failedLangs = new Set<string>();
@@ -129,7 +129,7 @@ export class TranslocoService implements OnDestroy {
     service = this;
     this.config = structuredClone(userConfig);
 
-    this.setAvailableLangs(this.config.availableLangs || []);
+    this.setAvailableLangs(this.config.availableLangs);
     this.setFallbackLangForMissingTranslation(this.config);
     this.setDefaultLang(this.config.defaultLang);
     this.lang = new BehaviorSubject<string>(this.getDefaultLang());
@@ -169,7 +169,7 @@ export class TranslocoService implements OnDestroy {
     return this;
   }
 
-  setAvailableLangs(langs: AvailableLangs) {
+  setAvailableLangs(langs: AvailableLangs | undefined) {
     this.availableLangs = langs;
   }
 
@@ -181,7 +181,7 @@ export class TranslocoService implements OnDestroy {
    * depending on how the available languages are set in your module.
    */
   getAvailableLangs() {
-    return this.availableLangs;
+    return this.availableLangs ?? [];
   }
 
   load(path: string, options: LoadOptions = {}): Observable<Translation> {
@@ -626,7 +626,11 @@ export class TranslocoService implements OnDestroy {
    * @internal
    */
   _isLangScoped(lang: string) {
-    return this.getAvailableLangsIds().indexOf(lang) === -1;
+    const availableLangsIds = this.getAvailableLangsIds();
+    if (!availableLangsIds) {
+      return true;
+    }
+    return availableLangsIds.indexOf(lang) === -1;
   }
 
   /**
@@ -636,7 +640,11 @@ export class TranslocoService implements OnDestroy {
    * False if the given string is not an available language.
    */
   isLang(lang: string): boolean {
-    return this.getAvailableLangsIds().indexOf(lang) !== -1;
+    const availableLangsIds = this.getAvailableLangsIds();
+    if (!availableLangsIds) {
+      return true;
+    }
+    return availableLangsIds.indexOf(lang) !== -1;
   }
 
   /**
@@ -701,8 +709,12 @@ export class TranslocoService implements OnDestroy {
     return size(this.getTranslation(lang));
   }
 
-  private getAvailableLangsIds(): string[] {
-    const first = this.getAvailableLangs()[0];
+  private getAvailableLangsIds(): string[] | null {
+    const first = this.getAvailableLangs()?.[0];
+    
+    if (isNil(first)) {
+      return null;
+    }
 
     if (isString(first)) {
       return this.getAvailableLangs() as string[];
diff --git a/libs/transloco/src/lib/types.ts b/libs/transloco/src/lib/types.ts
index 7ef9f37c1..0248b6b45 100644
--- a/libs/transloco/src/lib/types.ts
+++ b/libs/transloco/src/lib/types.ts
@@ -30,7 +30,7 @@ export interface LangDefinition {
   id: string;
   label: string;
 }
-export type AvailableLangs = string[] | LangDefinition[];
+export type AvailableLangs = string[] | LangDefinition[] | null;
 export interface SetTranslationOptions {
   merge?: boolean;
   emitChange?: boolean;