diff --git a/README.md b/README.md
index cf81236a0..52792e3c7 100644
--- a/README.md
+++ b/README.md
@@ -92,8 +92,8 @@ Validator                               | Description
 **contains(str, seed [, options ])**    | check if the string contains the seed.<br/><br/>`options` is an object that defaults to `{ ignoreCase: false, minOccurrences: 1 }`.<br />Options: <br/> `ignoreCase`: Ignore case when doing comparison, default false<br/>`minOccurences`: Minimum number of occurrences for the seed in the string. Defaults to 1.
 **equals(str, comparison)**             | check if the string matches the comparison.
 **isAfter(str [, date])**               | check if the string is a date that's after the specified date (defaults to now).
-**isAlpha(str [, locale, options])**    | check if the string contains only letters (a-zA-Z).<br/><br/>Locale is one of `['ar', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-EG', 'ar-IQ', 'ar-JO', 'ar-KW', 'ar-LB', 'ar-LY', 'ar-MA', 'ar-QA', 'ar-QM', 'ar-SA', 'ar-SD', 'ar-SY', 'ar-TN', 'ar-YE', 'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'el-GR', 'en-AU', 'en-GB', 'en-HK', 'en-IN', 'en-NZ', 'en-US', 'en-ZA', 'en-ZM', 'es-ES', 'fa-IR', 'fi-FI', 'fr-CA', 'fr-FR', 'he', 'hi-IN', 'hu-HU', 'it-IT', 'ku-IQ', 'nb-NO', 'nl-NL', 'nn-NO', 'pl-PL', 'pt-BR', 'pt-PT', 'ru-RU', 'sl-SI', 'sk-SK', 'sr-RS', 'sr-RS@latin', 'sv-SE', 'tr-TR', 'uk-UA']`) and defaults to `en-US`. Locale list is `validator.isAlphaLocales`. options is an optional object that can be supplied with the following key(s): ignore which can either be a String or RegExp of characters to be ignored e.g. " -" will ignore spaces and -'s.
-**isAlphanumeric(str [, locale, options])**      | check if the string contains only letters and numbers (a-zA-Z0-9).<br/><br/>Locale is one of `['ar', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-EG', 'ar-IQ', 'ar-JO', 'ar-KW', 'ar-LB', 'ar-LY', 'ar-MA', 'ar-QA', 'ar-QM', 'ar-SA', 'ar-SD', 'ar-SY', 'ar-TN', 'ar-YE', 'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'el-GR', 'en-AU', 'en-GB', 'en-HK', 'en-IN', 'en-NZ', 'en-US', 'en-ZA', 'en-ZM', 'es-ES', 'fa-IR', 'fi-FI', 'fr-CA', 'fr-FR', 'he', 'hi-IN', 'hu-HU', 'it-IT', 'ku-IQ', 'nb-NO', 'nl-NL', 'nn-NO', 'pl-PL', 'pt-BR', 'pt-PT', 'ru-RU', 'sl-SI', 'sk-SK', 'sr-RS', 'sr-RS@latin', 'sv-SE', 'tr-TR', 'uk-UA']`) and defaults to `en-US`. Locale list is `validator.isAlphanumericLocales`. options is an optional object that can be supplied with the following key(s): ignore which can either be a String or RegExp of characters to be ignored e.g. " -" will ignore spaces and -'s.
+**isAlpha(str [, locale, options])**    | check if the string contains only letters (a-zA-Z).<br/><br/>Locale is one of `['ar', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-EG', 'ar-IQ', 'ar-JO', 'ar-KW', 'ar-LB', 'ar-LY', 'ar-MA', 'ar-QA', 'ar-QM', 'ar-SA', 'ar-SD', 'ar-SY', 'ar-TN', 'ar-YE', 'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'el-GR', 'en-AU', 'en-GB', 'en-HK', 'en-IN', 'en-NZ', 'en-US', 'en-ZA', 'en-ZM', 'es-ES', 'fa-IR', 'fi-FI', 'fr-CA', 'fr-FR', 'he', 'hi-IN', 'hu-HU', 'it-IT', 'ku-IQ', 'nb-NO', 'nl-NL', 'nn-NO', 'pl-PL', 'pt-BR', 'pt-PT', 'ru-RU', 'si-LK', 'sl-SI', 'sk-SK', 'sr-RS', 'sr-RS@latin', 'sv-SE', 'tr-TR', 'uk-UA']`) and defaults to `en-US`. Locale list is `validator.isAlphaLocales`. options is an optional object that can be supplied with the following key(s): ignore which can either be a String or RegExp of characters to be ignored e.g. " -" will ignore spaces and -'s.
+**isAlphanumeric(str [, locale, options])**      | check if the string contains only letters and numbers (a-zA-Z0-9).<br/><br/>Locale is one of `['ar', 'ar-AE', 'ar-BH', 'ar-DZ', 'ar-EG', 'ar-IQ', 'ar-JO', 'ar-KW', 'ar-LB', 'ar-LY', 'ar-MA', 'ar-QA', 'ar-QM', 'ar-SA', 'ar-SD', 'ar-SY', 'ar-TN', 'ar-YE', 'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'el-GR', 'en-AU', 'en-GB', 'en-HK', 'en-IN', 'en-NZ', 'en-US', 'en-ZA', 'en-ZM', 'es-ES', 'fa-IR', 'fi-FI', 'fr-CA', 'fr-FR', 'he', 'hi-IN', 'hu-HU', 'it-IT', 'ku-IQ', 'nb-NO', 'nl-NL', 'nn-NO', 'pl-PL', 'pt-BR', 'pt-PT', 'ru-RU', 'si-LK', 'sl-SI', 'sk-SK', 'sr-RS', 'sr-RS@latin', 'sv-SE', 'tr-TR', 'uk-UA']`) and defaults to `en-US`. Locale list is `validator.isAlphanumericLocales`. options is an optional object that can be supplied with the following key(s): ignore which can either be a String or RegExp of characters to be ignored e.g. " -" will ignore spaces and -'s.
 **isAscii(str)**                        | check if the string contains ASCII chars only.
 **isBase32(str [, options])**           | check if a string is base32 encoded. `options` is optional and defaults to `{crockford: false}`.<br/> When `crockford` is true it tests the given base32 encoded string using [Crockford's base32 alternative](http://www.crockford.com/base32.html).
 **isBase58(str)**                       | check if a string is base58 encoded.
diff --git a/src/lib/alpha.js b/src/lib/alpha.js
index d663eded0..445ef85b0 100644
--- a/src/lib/alpha.js
+++ b/src/lib/alpha.js
@@ -32,6 +32,7 @@ export const alpha = {
   he: /^[א-ת]+$/,
   fa: /^['آاءأؤئبپتثجچحخدذرزژسشصضطظعغفقکگلمنوهةی']+$/i,
   'hi-IN': /^[\u0900-\u0961]+[\u0972-\u097F]*$/i,
+  'si-LK': /^[\u0D80-\u0DFF]+$/,
 };
 
 export const alphanumeric = {
@@ -67,6 +68,7 @@ export const alphanumeric = {
   he: /^[0-9א-ת]+$/,
   fa: /^['0-9آاءأؤئبپتثجچحخدذرزژسشصضطظعغفقکگلمنوهةی۱۲۳۴۵۶۷۸۹۰']+$/i,
   'hi-IN': /^[\u0900-\u0963]+[\u0966-\u097F]*$/i,
+  'si-LK': /^[0-9\u0D80-\u0DFF]+$/,
 };
 
 export const decimal = {
@@ -112,7 +114,7 @@ export const dotDecimal = ['ar-EG', 'ar-LB', 'ar-LY'];
 export const commaDecimal = [
   'bg-BG', 'cs-CZ', 'da-DK', 'de-DE', 'el-GR', 'en-ZM', 'es-ES', 'fr-CA', 'fr-FR',
   'id-ID', 'it-IT', 'ku-IQ', 'hi-IN', 'hu-HU', 'nb-NO', 'nn-NO', 'nl-NL', 'pl-PL', 'pt-PT',
-  'ru-RU', 'sl-SI', 'sr-RS@latin', 'sr-RS', 'sv-SE', 'tr-TR', 'uk-UA', 'vi-VN',
+  'ru-RU', 'si-LK', 'sl-SI', 'sr-RS@latin', 'sr-RS', 'sv-SE', 'tr-TR', 'uk-UA', 'vi-VN',
 ];
 
 for (let i = 0; i < dotDecimal.length; i++) {
diff --git a/test/validators.js b/test/validators.js
index 0561c0fb6..42c54873e 100644
--- a/test/validators.js
+++ b/test/validators.js
@@ -1938,6 +1938,26 @@ describe('Validators', () => {
     });
   });
 
+  it('should validate Sinhala alpha strings', () => {
+    test({
+      validator: 'isAlpha',
+      args: ['si-LK'],
+      valid: [
+        'චතුර',
+        'කචටදබ',
+        'ඎඏදාෛපසුගො',
+      ],
+      invalid: [
+        'ஆஐअतක',
+        'කචට 12',
+        ' ඎ ',
+        'abc1',
+        'abc',
+        '',
+      ],
+    });
+  });
+
   it('should error on invalid locale', () => {
     test({
       validator: 'isAlpha',
@@ -2525,6 +2545,27 @@ describe('Validators', () => {
     });
   });
 
+  it('should validate Sinhala alphanumeric strings', () => {
+    test({
+      validator: 'isAlphanumeric',
+      args: ['si-LK'],
+      valid: [
+        'චතුර',
+        'කචට12',
+        'ඎඏදාෛපසුගො2',
+        '1234',
+      ],
+      invalid: [
+        'ஆஐअतක',
+        'කචට 12',
+        ' ඎ ',
+        'a1234',
+        'abc',
+        '',
+      ],
+    });
+  });
+
   it('should error on invalid locale', () => {
     test({
       validator: 'isAlphanumeric',