diff --git a/main/src/main/java/sbt/internal/XMainConfiguration.java b/main/src/main/java/sbt/internal/XMainConfiguration.java
index 50e84c08c..6a70f2edf 100644
--- a/main/src/main/java/sbt/internal/XMainConfiguration.java
+++ b/main/src/main/java/sbt/internal/XMainConfiguration.java
@@ -12,6 +12,7 @@ import java.io.File;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.net.URI;
 import java.net.URL;
 import xsbti.*;
 
@@ -72,7 +73,7 @@ public class XMainConfiguration {
       URL url = baseLoader.getResource(className);
       String path = url.toString().replaceAll(className.concat("$"), "");
       URL[] urlArray = new URL[1];
-      urlArray[0] = new URL(path);
+      urlArray[0] = new URI(path).toURL();
       ClassLoader topLoader = configuration.provider().scalaProvider().launcher().topLoader();
       // This loader doesn't have the scala library in it so it's critical that none of the code
       // in this file use the scala library.
diff --git a/main/src/main/scala/sbt/internal/APIMappings.scala b/main/src/main/scala/sbt/internal/APIMappings.scala
index 18291c643..64fe2849d 100644
--- a/main/src/main/scala/sbt/internal/APIMappings.scala
+++ b/main/src/main/scala/sbt/internal/APIMappings.scala
@@ -17,6 +17,7 @@ import sbt.librarymanagement.ModuleID
 
 import sbt.internal.util.Attributed
 import sbt.util.Logger
+import java.net.URI
 
 private[sbt] object APIMappings {
   def extract(cp: Seq[Attributed[File]], log: Logger): Seq[(File, URL)] =
@@ -38,7 +39,7 @@ private[sbt] object APIMappings {
     } yield (entry, u)
 
   private[this] def parseURL(s: String, forEntry: File, log: Logger): Option[URL] =
-    try Some(new URL(s))
+    try Some(new URI(s).toURL)
     catch {
       case e: MalformedURLException =>
         log.warn(s"Invalid API base URL '$s' for classpath entry '$forEntry': ${e.toString}")
diff --git a/main/src/main/scala/sbt/internal/InstallSbtn.scala b/main/src/main/scala/sbt/internal/InstallSbtn.scala
index 151fa2a28..827826992 100644
--- a/main/src/main/scala/sbt/internal/InstallSbtn.scala
+++ b/main/src/main/scala/sbt/internal/InstallSbtn.scala
@@ -13,7 +13,7 @@ import Def._
 import Keys.{ sbtVersion, state, terminal }
 
 import java.io.{ File, FileInputStream, FileOutputStream, InputStream, IOException }
-import java.net.URL
+import java.net.URI
 import java.nio.file.{ Files, Path }
 import java.util.zip.ZipInputStream
 import sbt.io.IO
@@ -95,7 +95,7 @@ private[sbt] object InstallSbtn {
   }
   private[this] def downloadRelease(term: Terminal, version: String, location: Path): Unit = {
     val zip = s"https://github.com/sbt/sbt/releases/download/v$version/sbt-$version.zip"
-    val url = new URL(zip)
+    val url = new URI(zip).toURL
     term.printStream.println(s"downloading $zip to $location")
     transfer(url.openStream(), location)
   }
@@ -133,7 +133,7 @@ private[sbt] object InstallSbtn {
   private[this] def downloadCompletion(completion: String, version: String, target: Path): Unit = {
     Files.createDirectories(target.getParent)
     val comp = s"https://raw.githubusercontent.com/sbt/sbt/v$version/client/completions/$completion"
-    transfer(new URL(comp).openStream, target)
+    transfer(new URI(comp).toURL.openStream, target)
   }
   private[this] def setupShell(
       shell: String,
diff --git a/sbt-app/src/main/scala/package.scala b/sbt-app/src/main/scala/package.scala
index 0bb7f7f24..b05d0a305 100644
--- a/sbt-app/src/main/scala/package.scala
+++ b/sbt-app/src/main/scala/package.scala
@@ -32,7 +32,7 @@ package object sbt
   // IO
   def uri(s: String): URI = new URI(s)
   def file(s: String): File = new File(s)
-  def url(s: String): URL = new URL(s)
+  def url(s: String): URL = new URI(s).toURL
   implicit def fileToRichFile(file: File): sbt.io.RichFile = new sbt.io.RichFile(file)
   implicit def filesToFinder(cc: Traversable[File]): sbt.io.PathFinder =
     sbt.io.PathFinder.strict(cc)
diff --git a/sbt-app/src/sbt-test/dependency-management/cache-update/build.sbt b/sbt-app/src/sbt-test/dependency-management/cache-update/build.sbt
index 47d24a502..4e14962ef 100644
--- a/sbt-app/src/sbt-test/dependency-management/cache-update/build.sbt
+++ b/sbt-app/src/sbt-test/dependency-management/cache-update/build.sbt
@@ -20,7 +20,7 @@ lazy val root = (project in file("."))
       ),
       version := "0.3.1-SNAPSHOT",
       description := "An HTTP client for Scala with Async Http Client underneath.",
-      licenses := Seq("Apache 2" -> new URL("http://www.apache.org/licenses/LICENSE-2.0.txt")),
+      licenses := Seq("Apache 2" -> url("http://www.apache.org/licenses/LICENSE-2.0.txt")),
     )),
     ivyPaths := IvyPaths(
       (baseDirectory in ThisBuild).value,