diff --git a/api.js b/api.js
index ab69e5e616..1bfc46f2e4 100644
--- a/api.js
+++ b/api.js
@@ -807,7 +807,7 @@ API.prototype.getBrowserTimingHeader = function getBrowserTimingHeader(options =
      * Only the first 13 chars of the license should be used for hashing with
      * the transaction name.
      */
-    const key = config.license_key.substr(0, 13)
+    const key = config.license_key.substring(0, 13)
     rumHash.transactionName = hashes.obfuscateNameUsingKey(name, key)
 
     rumHash.queueTime = trans.queueTime
diff --git a/bin/create-docs-pr.js b/bin/create-docs-pr.js
index ceea213c7b..6db947facd 100644
--- a/bin/create-docs-pr.js
+++ b/bin/create-docs-pr.js
@@ -241,7 +241,7 @@ function formatReleaseNotes(releaseDate, version, body, frontmatter) {
     '---',
     'subject: Node.js agent',
     `releaseDate: '${releaseDate}'`,
-    `version: ${version.substr(1)}`, // remove the `v` from start of version
+    `version: ${version.substring(1)}`, // remove the `v` from start of version
     `downloadLink: 'https://www.npmjs.com/package/newrelic'`,
     `security: ${frontmatter.security}`,
     `bugs: ${frontmatter.bugfixes}`,
@@ -279,7 +279,7 @@ function addReleaseNotesFile(body, version) {
 
 function getFileName(version) {
   // change `v0.0.0` to `0-0-0`
-  version = version.substr(1).replace(/\./g, '-')
+  version = version.substring(1).replace(/\./g, '-')
   const FILE = `node-agent-${version}.mdx`
   return `${RELEASE_NOTES_PATH}/${FILE}`
 }
diff --git a/lib/config/attribute-filter.js b/lib/config/attribute-filter.js
index 468773cfbc..2cfa623e3e 100644
--- a/lib/config/attribute-filter.js
+++ b/lib/config/attribute-filter.js
@@ -367,7 +367,7 @@ function _convertRulesToRegex(rules) {
           if (i !== r.length - 1) {
             v += '.'
           } else if (/\\\*$/.test(v)) {
-            v = v.substr(0, v.length - 2)
+            v = v.substring(0, v.length - 2)
           }
 
           const idx = c.findIndex(function findV(a) {
diff --git a/lib/instrumentation/aws-sdk/util.js b/lib/instrumentation/aws-sdk/util.js
index c5b4912a8a..194b2b91b5 100644
--- a/lib/instrumentation/aws-sdk/util.js
+++ b/lib/instrumentation/aws-sdk/util.js
@@ -14,7 +14,7 @@ function grabLastUrlSegment(url = '/') {
   // string for null, undefined, NaN etc.
   url = '' + (url || '/')
   const lastSlashIndex = url.lastIndexOf('/')
-  return url.substr(lastSlashIndex + 1)
+  return url.substring(lastSlashIndex + 1)
 }
 
 /**
diff --git a/lib/shim/datastore-shim.js b/lib/shim/datastore-shim.js
index 82bee9e62e..9c1b85bfcc 100644
--- a/lib/shim/datastore-shim.js
+++ b/lib/shim/datastore-shim.js
@@ -376,10 +376,10 @@ function parseQuery(query, nodule) {
   // strip enclosing special characters from collection (table) name
   if (typeof collection === 'string' && collection.length > 2) {
     if (/^[\[{'"`]/.test(collection)) {
-      collection = collection.substr(1)
+      collection = collection.substring(1)
     }
     if (/[\]}'"`]$/.test(collection)) {
-      collection = collection.substr(0, collection.length - 1)
+      collection = collection.substring(0, collection.length - 1)
     }
   }
 
diff --git a/lib/transaction/name-state.js b/lib/transaction/name-state.js
index 3bcd746c75..e1eb4d9ac8 100644
--- a/lib/transaction/name-state.js
+++ b/lib/transaction/name-state.js
@@ -187,7 +187,7 @@ NameState.prototype.getPath = function getPath() {
       if (a[0] !== '/' && path[path.length - 1] !== '/') {
         path += '/'
       } else if (a[0] === '/' && path[path.length - 1] === '/') {
-        a = a.substr(1)
+        a = a.substring(1)
       }
       path += a
     }
diff --git a/lib/util/hashes.js b/lib/util/hashes.js
index 9e269598ea..1439e0064a 100644
--- a/lib/util/hashes.js
+++ b/lib/util/hashes.js
@@ -41,7 +41,8 @@ function calculatePathHash(appName, pathName, referingPathHash) {
   const result = (rotated ^ hash) >>> 0
 
   // This is a trick to pad it out to 8 chars regardless of length.
-  return ('00000000' + result.toString(16)).substr(-8)
+  const str = '00000000' + result.toString(16)
+  return str.substring(str.length - 8)
 }
 
 function getHash(appName, txName) {
@@ -78,7 +79,7 @@ function int32ToByteArray(int32) {
 // Lookup table for converting byte values to hex
 const byteToHex = []
 for (let i = 0; i < 256; ++i) {
-  byteToHex[i] = (i + 0x100).toString(16).substr(1)
+  byteToHex[i] = (i + 0x100).toString(16).substring(1)
 }
 
 function makeId(length = 16) {
diff --git a/lib/utilization/docker-info.js b/lib/utilization/docker-info.js
index fe92783d0c..eeb8843c28 100644
--- a/lib/utilization/docker-info.js
+++ b/lib/utilization/docker-info.js
@@ -41,7 +41,7 @@ module.exports.getBootId = function getBootId(agent, callback) {
     if (data.length !== 36) {
       bootIdError()
       if (data.length > 128) {
-        data = data.substr(0, 128)
+        data = data.substring(0, 128)
       }
     }
 
diff --git a/lib/utilization/gcp-info.js b/lib/utilization/gcp-info.js
index 990c4f73dd..380fd75d59 100644
--- a/lib/utilization/gcp-info.js
+++ b/lib/utilization/gcp-info.js
@@ -54,8 +54,10 @@ function fetchGCPInfo(agent, callback) {
         agent.metrics.getOrCreateMetric(NAMES.UTILIZATION.GCP_ERROR).incrementCallCount()
       } else {
         // normalize
-        results.machineType = results.machineType.substr(results.machineType.lastIndexOf('/') + 1)
-        results.zone = results.zone.substr(results.zone.lastIndexOf('/') + 1)
+        results.machineType = results.machineType.substring(
+          results.machineType.lastIndexOf('/') + 1
+        )
+        results.zone = results.zone.substring(results.zone.lastIndexOf('/') + 1)
 
         resultDict = results
       }
diff --git a/test/integration/instrumentation/http-rum.tap.js b/test/integration/instrumentation/http-rum.tap.js
index 87ab732785..b9ffc47386 100644
--- a/test/integration/instrumentation/http-rum.tap.js
+++ b/test/integration/instrumentation/http-rum.tap.js
@@ -56,14 +56,14 @@ test('custom naming rules should be applied early for RUM', function (t) {
     function done(res) {
       res.pipe(
         new StreamSink(function (err, header) {
-          t.equal(header.substr(0, 7), '<script', 'should generate RUM headers')
+          t.equal(header.substring(0, 7), '<script', 'should generate RUM headers')
           header.split(';').forEach(function (element) {
-            if (element.substr(0, DATA_PREFIX.length) === DATA_PREFIX) {
-              const dataString = element.substr(DATA_PREFIX.length, element.length)
+            if (element.substring(0, DATA_PREFIX.length) === DATA_PREFIX) {
+              const dataString = element.substring(DATA_PREFIX.length, element.length)
               const data = JSON.parse(dataString)
               const tx = hashes.deobfuscateNameUsingKey(
                 data.transactionName,
-                agent.config.license_key.substr(0, 13)
+                agent.config.license_key.substring(0, 13)
               )
               t.equal(tx, 'WebTransaction/NormalizedUri/WORKING', 'should normalize url before RUM')
             }
@@ -106,14 +106,14 @@ test('custom web transactions should have rules applied for RUM', function (t) {
 
   api.startWebTransaction('/test', function () {
     const header = api.getBrowserTimingHeader()
-    t.equal(header.substr(0, 7), '<script', 'should generate RUM headers')
+    t.equal(header.substring(0, 7), '<script', 'should generate RUM headers')
     header.split(';').forEach(function (element) {
-      if (element.substr(0, DATA_PREFIX.length) === DATA_PREFIX) {
-        const dataString = element.substr(DATA_PREFIX.length, element.length)
+      if (element.substring(0, DATA_PREFIX.length) === DATA_PREFIX) {
+        const dataString = element.substring(DATA_PREFIX.length, element.length)
         const data = JSON.parse(dataString)
         const tx = hashes.deobfuscateNameUsingKey(
           data.transactionName,
-          agent.config.license_key.substr(0, 13)
+          agent.config.license_key.substring(0, 13)
         )
         t.equal(tx, 'WebTransaction/NormalizedUri/WORKING', 'url normalized before RUM')
       }
diff --git a/test/unit/rum.test.js b/test/unit/rum.test.js
index 9c53c5f859..d45f84fd6d 100644
--- a/test/unit/rum.test.js
+++ b/test/unit/rum.test.js
@@ -230,7 +230,7 @@ tap.test('the RUM API', function (t) {
       t.ok(payload)
       const deobf = hashes.deobfuscateNameUsingKey(
         payload[1],
-        agent.config.license_key.substr(0, 13)
+        agent.config.license_key.substring(0, 13)
       )
       t.equal(JSON.parse(deobf).u.hello, 1)
       t.end()
diff --git a/test/versioned/express/render.tap.js b/test/versioned/express/render.tap.js
index d50abe0b15..ee3fc61337 100644
--- a/test/versioned/express/render.tap.js
+++ b/test/versioned/express/render.tap.js
@@ -234,7 +234,7 @@ function runTests(conf) {
 
       app.get(TEST_PATH, function (req, res) {
         const rum = api.getBrowserTimingHeader()
-        t.equal(rum.substr(0, 7), '<script')
+        t.equal(rum.substring(0, 7), '<script')
         res.render('index', { title: 'yo dawg', rum: rum })
       })
 
diff --git a/test/versioned/hapi/render.tap.js b/test/versioned/hapi/render.tap.js
index 738a1f8a4a..8fafbbf004 100644
--- a/test/versioned/hapi/render.tap.js
+++ b/test/versioned/hapi/render.tap.js
@@ -146,7 +146,7 @@ tap.test('agent instrumentation of Hapi', function (t) {
       path: '/test',
       handler: function (req, h) {
         const rum = api.getBrowserTimingHeader()
-        t.equal(rum.substr(0, 7), '<script')
+        t.equal(rum.substring(0, 7), '<script')
         return h.view('index', { title: 'yo dawg', rum: rum })
       }
     })
diff --git a/test/versioned/restify/pre-7/rum.tap.js b/test/versioned/restify/pre-7/rum.tap.js
index b342d187c8..0df9dcfe69 100644
--- a/test/versioned/restify/pre-7/rum.tap.js
+++ b/test/versioned/restify/pre-7/rum.tap.js
@@ -29,7 +29,7 @@ tap.test('Restify router introspection', function (t) {
 
   server.get('/test/:id', function (req, res, next) {
     const rum = api.getBrowserTimingHeader()
-    t.equal(rum.substr(0, 7), '<script')
+    t.equal(rum.substring(0, 7), '<script')
     res.send({ status: 'ok' })
     next()
   })
diff --git a/test/versioned/restify/rum.tap.js b/test/versioned/restify/rum.tap.js
index d629f77cee..4c0e7f5eca 100644
--- a/test/versioned/restify/rum.tap.js
+++ b/test/versioned/restify/rum.tap.js
@@ -29,7 +29,7 @@ tap.test('Restify router introspection', function (t) {
 
   server.get('/test/:id', function (req, res, next) {
     const rum = api.getBrowserTimingHeader()
-    t.equal(rum.substr(0, 7), '<script')
+    t.equal(rum.substring(0, 7), '<script')
     res.send({ status: 'ok' })
     next()
   })