diff --git a/.changeset/hip-beers-listen.md b/.changeset/hip-beers-listen.md
new file mode 100644
index 0000000..c2d4e4d
--- /dev/null
+++ b/.changeset/hip-beers-listen.md
@@ -0,0 +1,5 @@
+---
+"simple-stack-form": patch
+---
+
+Fix accidental form submission on client validation errors
diff --git a/examples/form/src/components/preact/Form.tsx b/examples/form/src/components/preact/Form.tsx
index 788f2d6..5691635 100644
--- a/examples/form/src/components/preact/Form.tsx
+++ b/examples/form/src/components/preact/Form.tsx
@@ -76,6 +76,7 @@ export function Form({
 						return formContext.trackAstroSubmitStatus();
 					}
 
+					e.preventDefault();
 					e.stopPropagation();
 					formContext.setValidationErrors(parsed.fieldErrors);
 				}}
diff --git a/examples/form/src/components/react/Form.tsx b/examples/form/src/components/react/Form.tsx
index 0a071d1..5c5e337 100644
--- a/examples/form/src/components/react/Form.tsx
+++ b/examples/form/src/components/react/Form.tsx
@@ -78,6 +78,7 @@ export function Form({
 						return formContext.trackAstroSubmitStatus();
 					}
 
+					e.preventDefault();
 					e.stopPropagation();
 					formContext.setValidationErrors(parsed.fieldErrors);
 				}}
diff --git a/packages/form/templates/preact/Form.tsx b/packages/form/templates/preact/Form.tsx
index 821e1a3..50f3a49 100644
--- a/packages/form/templates/preact/Form.tsx
+++ b/packages/form/templates/preact/Form.tsx
@@ -74,6 +74,7 @@ export function Form({
 						return formContext.trackAstroSubmitStatus();
 					}
 
+					e.preventDefault();
 					e.stopPropagation();
 					formContext.setValidationErrors(parsed.fieldErrors);
 				}}
diff --git a/packages/form/templates/react/Form.tsx b/packages/form/templates/react/Form.tsx
index 383844b..2aa8ced 100644
--- a/packages/form/templates/react/Form.tsx
+++ b/packages/form/templates/react/Form.tsx
@@ -78,6 +78,7 @@ export function Form({
 						return formContext.trackAstroSubmitStatus();
 					}
 
+					e.preventDefault();
 					e.stopPropagation();
 					formContext.setValidationErrors(parsed.fieldErrors);
 				}}