diff --git a/packages/core/src/FetchMock.ts b/packages/core/src/FetchMock.ts
index 46db9d0e..b5f8f47c 100644
--- a/packages/core/src/FetchMock.ts
+++ b/packages/core/src/FetchMock.ts
@@ -5,7 +5,6 @@ import CallHistory from './CallHistory.js';
 import * as requestUtils from './RequestUtils.js';
 
 export type FetchMockGlobalConfig = {
-	sendAsJson?: boolean;
 	includeContentLength?: boolean;
 	matchPartialBody?: boolean;
 	allowRelativeUrls?: boolean;
@@ -20,7 +19,6 @@ export type FetchMockConfig = FetchMockGlobalConfig & FetchImplementations;
 
 export const defaultFetchMockConfig: FetchMockConfig = {
 	includeContentLength: true,
-	sendAsJson: true,
 	matchPartialBody: false,
 	Request: globalThis.Request,
 	Response: globalThis.Response,
diff --git a/packages/core/src/Route.ts b/packages/core/src/Route.ts
index 1d10ff96..471d67b2 100644
--- a/packages/core/src/Route.ts
+++ b/packages/core/src/Route.ts
@@ -217,7 +217,7 @@ class Route {
 		if (!bodyIsBodyInit) {
 			if (typeof body === 'undefined') {
 				body = null
-			} else if (typeof body === 'object' && this.config.sendAsJson) {
+			} else if (typeof body === 'object') {
 				// convert to json if we need to
 				body = JSON.stringify(body);
 				if (!responseOptions.headers.has('Content-Type')) {
diff --git a/packages/core/src/__tests__/FetchMock/response-construction.test.js b/packages/core/src/__tests__/FetchMock/response-construction.test.js
index 6b5edd22..6ca20770 100644
--- a/packages/core/src/__tests__/FetchMock/response-construction.test.js
+++ b/packages/core/src/__tests__/FetchMock/response-construction.test.js
@@ -102,39 +102,6 @@ describe('response construction', () => {
 			const res = await fm.fetchHandler('http://a.com/');
 			expect(res.headers.get('content-type')).toEqual('application/json');
 		});
-
-		describe('sendAsJson option', () => {
-			it('convert object responses to json by default', async () => {
-				fm.route('*', { an: 'object' });
-				const res = await fm.fetchHandler('http://it.at.there');
-				expect(res.headers.get('content-type')).toEqual('application/json');
-			});
-
-			it("don't convert when configured false", async () => {
-				fm.config.sendAsJson = false;
-				fm.route('*', { an: 'object' });
-				const res = await fm.fetchHandler('http://it.at.there');
-				// can't check for existence as the spec says, in the browser, that
-				// a default value should be set
-				expect(res.headers.get('content-type')).not.toEqual('application/json');
-			});
-
-			it('local setting can override to true', async () => {
-				fm.config.sendAsJson = false;
-				fm.route('*', { an: 'object' }, { sendAsJson: true });
-				const res = await fm.fetchHandler('http://it.at.there');
-				expect(res.headers.get('content-type')).toEqual('application/json');
-			});
-
-			it('local setting can override to false', async () => {
-				fm.config.sendAsJson = true;
-				fm.route('*', { an: 'object' }, { sendAsJson: false });
-				const res = await fm.fetchHandler('http://it.at.there');
-				// can't check for existence as the spec says, in the browser, that
-				// a default value should be set
-				expect(res.headers.get('content-type')).not.toEqual('application/json');
-			});
-		});
 	});
 
 	it('respond with a complex response, including headers', async () => {
@@ -153,7 +120,7 @@ describe('response construction', () => {
 
 	if (typeof Buffer !== 'undefined') {
 		it('can respond with a buffer', () => {
-			fm.route(/a/, new Buffer('buffer'), { sendAsJson: false });
+			fm.route(/a/, new Buffer('buffer'));
 			return fm
 				.fetchHandler('http://a.com')
 				.then((res) => res.text())
@@ -165,7 +132,7 @@ describe('response construction', () => {
 
 	it('respond with blob', async () => {
 		const blob = new Blob();
-		fm.route('*', blob, { sendAsJson: false });
+		fm.route('*', blob);
 		const res = await fm.fetchHandler('http://a.com');
 		expect(res.status).to.equal(200);
 		const blobData = await res.blob();