diff --git a/packages/pg-connection-string/index.js b/packages/pg-connection-string/index.js
index 139cc17b1..ec10c5de8 100644
--- a/packages/pg-connection-string/index.js
+++ b/packages/pg-connection-string/index.js
@@ -36,8 +36,9 @@ function parse(str, options = {}) {
     throw err
   }
 
-  // We'd like to use Object.fromEntries() here but Node.js 10 does not support it
-  for (const entry of result.searchParams.entries()) {
+  // Like libpq, only percent-decode the query values: URLSearchParams would turn a literal
+  // `+` into a space. We'd like to use Object.fromEntries() here but Node.js 10 does not support it
+  for (const entry of new URLSearchParams(result.search.replace(/\+/g, '%2B')).entries()) {
     config[entry[0]] = entry[1]
   }
 
diff --git a/packages/pg-connection-string/test/parse.ts b/packages/pg-connection-string/test/parse.ts
index 562c3ece0..ac831200a 100644
--- a/packages/pg-connection-string/test/parse.ts
+++ b/packages/pg-connection-string/test/parse.ts
@@ -192,6 +192,15 @@ describe('parse', function () {
     subject.fallback_application_name?.should.equal('TheAppFallback')
   })
 
+  it('configuration parameters keep a literal plus sign', function () {
+    const connectionString = 'pg:///?application_name=a+b&user=c+d&password=e+f&options=g%2Bh%20i'
+    const subject = parse(connectionString)
+    subject.application_name?.should.equal('a+b')
+    subject.user?.should.equal('c+d')
+    subject.password?.should.equal('e+f')
+    subject.options?.should.equal('g+h i')
+  })
+
   it('configuration parameter options', function () {
     const connectionString = 'pg:///?options=-c geqo=off'
     const subject = parse(connectionString)