diff --git a/src/compiler/compile/Component.ts b/src/compiler/compile/Component.ts
index 9822529ece61..d4b446f440a2 100644
--- a/src/compiler/compile/Component.ts
+++ b/src/compiler/compile/Component.ts
@@ -132,7 +132,8 @@ export default class Component {
 			source,
 			ast,
 			compile_options.filename,
-			compile_options.dev
+			compile_options.dev,
+			compile_options.cssPrefix
 		);
 		this.stylesheet.validate(this);
 
diff --git a/src/compiler/compile/css/Stylesheet.ts b/src/compiler/compile/css/Stylesheet.ts
index 246dab0f1219..cf99fc88e7a9 100644
--- a/src/compiler/compile/css/Stylesheet.ts
+++ b/src/compiler/compile/css/Stylesheet.ts
@@ -291,14 +291,14 @@ export default class Stylesheet {
 
 	nodes_with_css_class: Set<CssNode> = new Set();
 
-	constructor(source: string, ast: Ast, filename: string, dev: boolean) {
+	constructor(source: string, ast: Ast, filename: string, dev: boolean, cssPrefix: string) {
 		this.source = source;
 		this.ast = ast;
 		this.filename = filename;
 		this.dev = dev;
 
 		if (ast.css && ast.css.children.length) {
-			this.id = `svelte-${hash(ast.css.content.styles)}`;
+			this.id = `${cssPrefix}-${hash(ast.css.content.styles)}`;
 
 			this.has_styles = true;
 
diff --git a/src/compiler/compile/index.ts b/src/compiler/compile/index.ts
index 12b161aeeb0e..24e18430e45d 100644
--- a/src/compiler/compile/index.ts
+++ b/src/compiler/compile/index.ts
@@ -26,7 +26,8 @@ const valid_options = [
 	'css',
 	'loopGuardTimeout',
 	'preserveComments',
-	'preserveWhitespace'
+	'preserveWhitespace',
+	'cssPrefix'
 ];
 
 function validate_options(options: CompileOptions, warnings: Warning[]) {
@@ -68,7 +69,7 @@ function validate_options(options: CompileOptions, warnings: Warning[]) {
 }
 
 export default function compile(source: string, options: CompileOptions = {}) {
-	options = assign({ generate: 'dom', dev: false }, options);
+	options = assign({ generate: 'dom', dev: false, cssPrefix: 'svelte' }, options);
 
 	const stats = new Stats();
 	const warnings = [];
diff --git a/src/compiler/interfaces.ts b/src/compiler/interfaces.ts
index a5e286462ff3..2fb1ebcb0e37 100644
--- a/src/compiler/interfaces.ts
+++ b/src/compiler/interfaces.ts
@@ -126,6 +126,7 @@ export interface CompileOptions {
 
 	preserveComments?: boolean;
 	preserveWhitespace?: boolean;
+	cssPrefix?: string;
 }
 
 export interface ParserOptions {
diff --git a/test/css/index.js b/test/css/index.js
index dc17314597fa..4845018b3f9f 100644
--- a/test/css/index.js
+++ b/test/css/index.js
@@ -84,7 +84,9 @@ describe('css', () => {
 				css: read(`${__dirname}/samples/${dir}/expected.css`)
 			};
 
-			const actual_css = dom.css.code.replace(/svelte(-ref)?-[a-z0-9]+/g, (m, $1) => $1 ? m : 'svelte-xyz');
+			const cssPrefix = config.compileOptions && config.compileOptions.cssPrefix || 'svelte';
+			const regexp = new RegExp(`${cssPrefix}(-ref)?-[a-z0-9]+`, 'g');
+			const actual_css = dom.css.code.replace(regexp, (m, $1) => $1 ? m : 'svelte-xyz');
 			try {
 				assert.equal(actual_css, expected.css);
 			} catch (error) {
diff --git a/test/css/samples/custom-css-prefix/_config.js b/test/css/samples/custom-css-prefix/_config.js
new file mode 100644
index 000000000000..b85e3ae5a77e
--- /dev/null
+++ b/test/css/samples/custom-css-prefix/_config.js
@@ -0,0 +1,5 @@
+export default {
+    compileOptions: {
+        cssPrefix: 'sv'
+    }
+};
\ No newline at end of file
diff --git a/test/css/samples/custom-css-prefix/expected.css b/test/css/samples/custom-css-prefix/expected.css
new file mode 100644
index 000000000000..d466e8df9658
--- /dev/null
+++ b/test/css/samples/custom-css-prefix/expected.css
@@ -0,0 +1 @@
+div.svelte-xyz{color:red}
\ No newline at end of file
diff --git a/test/css/samples/custom-css-prefix/input.svelte b/test/css/samples/custom-css-prefix/input.svelte
new file mode 100644
index 000000000000..c87862c09306
--- /dev/null
+++ b/test/css/samples/custom-css-prefix/input.svelte
@@ -0,0 +1,7 @@
+<div>red</div>
+
+<style>
+	div {
+		color: red;
+	}
+</style>
\ No newline at end of file