diff --git a/.changeset/popular-chairs-pull.md b/.changeset/popular-chairs-pull.md
new file mode 100644
index 000000000000..570883ee0184
--- /dev/null
+++ b/.changeset/popular-chairs-pull.md
@@ -0,0 +1,6 @@
+---
+"@sveltejs/adapter-cloudflare-workers": patch
+"@sveltejs/adapter-cloudflare": patch
+---
+
+fix: add `workerd` to esbuild conditions
diff --git a/packages/adapter-cloudflare-workers/index.js b/packages/adapter-cloudflare-workers/index.js
index f9237e44dbb7..40962940bea3 100644
--- a/packages/adapter-cloudflare-workers/index.js
+++ b/packages/adapter-cloudflare-workers/index.js
@@ -86,7 +86,8 @@ export default function ({ config = 'wrangler.toml' } = {}) {
 			try {
 				const result = await esbuild.build({
 					platform: 'browser',
-					conditions: ['worker', 'browser'],
+					// https://github.com/cloudflare/workers-sdk/blob/a12b2786ce745f24475174bcec994ad691e65b0f/packages/wrangler/src/deployment-bundle/bundle.ts#L35-L36
+					conditions: ['workerd', 'worker', 'browser'],
 					sourcemap: 'linked',
 					target: 'es2022',
 					entryPoints: [`${tmp}/entry.js`],
diff --git a/packages/adapter-cloudflare/index.js b/packages/adapter-cloudflare/index.js
index 16adc5f88e72..30603c50030e 100644
--- a/packages/adapter-cloudflare/index.js
+++ b/packages/adapter-cloudflare/index.js
@@ -74,7 +74,8 @@ export default function (options = {}) {
 			try {
 				const result = await esbuild.build({
 					platform: 'browser',
-					conditions: ['worker', 'browser'],
+					// https://github.com/cloudflare/workers-sdk/blob/a12b2786ce745f24475174bcec994ad691e65b0f/packages/wrangler/src/deployment-bundle/bundle.ts#L35-L36
+					conditions: ['workerd', 'worker', 'browser'],
 					sourcemap: 'linked',
 					target: 'es2022',
 					entryPoints: [`${tmp}/_worker.js`],