diff --git a/README.md b/README.md
index a79da49..9e2cbef 100644
--- a/README.md
+++ b/README.md
@@ -872,4 +872,4 @@ tach http://example.com
 | `--trace`                   | `false`                                 | Enable performance tracing ([details](#performance-traces))                                                                                                        |
 | `--trace-log-dir`           | `${cwd}/logs`                           | The directory to put tracing log files. Defaults to `${cwd}/logs`.                                                                                                 |
 | `--trace-cat`               | [default categories](./src/defaults.ts) | The tracing categories to record. Should be a string of comma-separated category names                                                                             |
-| `--partition`               | _(none)_                                | Use `"measurement"` to partition a single large results table into multiple tables for each [measurement](#measurement-modes).                                     |
+| `--partition`               | `"none"`                                | Use `"measurement"` to partition a single large results table into multiple tables for each [measurement](#measurement-modes).                                     |
diff --git a/src/config.ts b/src/config.ts
index 7e8d3a8..90e42bc 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -36,7 +36,7 @@ export interface Config {
   forceCleanNpmInstall: boolean;
   csvFileStats: string;
   csvFileRaw: string;
-  partition?: 'measurement';
+  partition: 'none' | 'measurement';
 }
 
 export async function makeConfig(opts: Opts): Promise<Config> {
@@ -176,7 +176,8 @@ export function applyDefaults(partial: Partial<Config>): Config {
         : defaults.resolveBareModules,
     root: partial.root !== undefined ? partial.root : defaults.root,
     timeout: partial.timeout !== undefined ? partial.timeout : defaults.timeout,
-    partition: partial.partition,
+    partition:
+      partial.partition !== undefined ? partial.partition : defaults.partition,
   };
 }
 
diff --git a/src/configfile.ts b/src/configfile.ts
index 4970562..d6a321a 100644
--- a/src/configfile.ts
+++ b/src/configfile.ts
@@ -387,9 +387,12 @@ export async function parseConfigFile(
   }
 
   if (validated.partition !== undefined) {
-    if (validated.partition !== 'measurement') {
+    if (
+      validated.partition !== 'measurement' &&
+      validated.partition !== 'none'
+    ) {
       throw new Error(
-        `The "partition" setting only accepts "measurement" as an option.`
+        `The "partition" setting only accepts "measurement" or "none" as an option.`
       );
     }
   }
diff --git a/src/defaults.ts b/src/defaults.ts
index b9a3edd..557268b 100644
--- a/src/defaults.ts
+++ b/src/defaults.ts
@@ -20,7 +20,7 @@ export const mode = 'automatic';
 export const resolveBareModules = true;
 export const forceCleanNpmInstall = false;
 export const measurementExpression = 'window.tachometerResult';
-export const partition = '';
+export const partition = 'none';
 export const traceLogDir = path.join(process.cwd(), 'logs');
 export const traceCategories = [
   'blink',
diff --git a/src/test/config_test.ts b/src/test/config_test.ts
index ab081f4..1d185bd 100644
--- a/src/test/config_test.ts
+++ b/src/test/config_test.ts
@@ -45,7 +45,7 @@ suite('makeConfig', function () {
       csvFileStats: '',
       csvFileRaw: '',
       githubCheck: undefined,
-      partition: undefined,
+      partition: 'none',
       benchmarks: [
         {
           browser: {
@@ -91,7 +91,7 @@ suite('makeConfig', function () {
       csvFileRaw: '',
       // TODO(aomarks) Be consistent about undefined vs unset.
       githubCheck: undefined,
-      partition: undefined,
+      partition: 'none',
       benchmarks: [
         {
           browser: {
@@ -137,7 +137,7 @@ suite('makeConfig', function () {
       csvFileStats: '',
       csvFileRaw: '',
       githubCheck: undefined,
-      partition: undefined,
+      partition: 'none',
       benchmarks: [
         {
           browser: {
@@ -190,7 +190,7 @@ suite('makeConfig', function () {
       remoteAccessibleHost: '',
       // TODO(aomarks) Be consistent about undefined vs unset.
       githubCheck: undefined,
-      partition: undefined,
+      partition: 'none',
       benchmarks: [
         {
           browser: {
@@ -224,7 +224,7 @@ suite('makeConfig', function () {
     const expected: Config = {
       mode: 'automatic',
       csvFileStats: '',
-      partition: undefined,
+      partition: 'none',
       csvFileRaw: '',
       jsonFile: '',
       legacyJsonFile: '',
diff --git a/src/test/format_test.ts b/src/test/format_test.ts
index 6c4632b..511ad78 100644
--- a/src/test/format_test.ts
+++ b/src/test/format_test.ts
@@ -227,7 +227,7 @@ suite('format', () => {
     assert.equal(actual, expected.trim() + '\n');
   });
 
-  test('multiple measurements, partition: undefined', async () => {
+  test('multiple measurements, partition: "none"', async () => {
     const config: ConfigFile = {
       benchmarks: [
         {