diff --git a/compiler/src/errors/output_bytes.rs b/compiler/src/errors/output_bytes.rs
index d07af02bfa..ee1366944e 100644
--- a/compiler/src/errors/output_bytes.rs
+++ b/compiler/src/errors/output_bytes.rs
@@ -14,7 +14,8 @@
 // You should have received a copy of the GNU General Public License
 // along with the Leo library. If not, see <https://www.gnu.org/licenses/>.
 
-use leo_ast::{Error as FormattedError, Span};
+use crate::errors::ValueError;
+use leo_ast::{Error as FormattedError, Span, Type};
 
 use std::path::Path;
 
@@ -22,12 +23,16 @@ use std::path::Path;
 pub enum OutputBytesError {
     #[error("{}", _0)]
     Error(#[from] FormattedError),
+
+    #[error("{}", _0)]
+    ValueError(#[from] ValueError),
 }
 
 impl OutputBytesError {
     pub fn set_path(&mut self, path: &Path) {
         match self {
             OutputBytesError::Error(error) => error.set_path(path),
+            OutputBytesError::ValueError(error) => error.set_path(path),
         }
     }
 
@@ -40,4 +45,13 @@ impl OutputBytesError {
 
         Self::new_from_span(message, span)
     }
+
+    pub fn mismatched_output_types(left: Type, right: Type, span: Span) -> Self {
+        let message = format!(
+            "Mismatched types. Expected register output type `{}`, found type `{}`.",
+            left, right
+        );
+
+        Self::new_from_span(message, span)
+    }
 }
diff --git a/compiler/src/output/output_bytes.rs b/compiler/src/output/output_bytes.rs
index db41582b22..c8b5578a61 100644
--- a/compiler/src/output/output_bytes.rs
+++ b/compiler/src/output/output_bytes.rs
@@ -63,10 +63,22 @@ impl OutputBytes {
         // format: "token_id: u64 = 1u64;"
         for (parameter, value) in register_values.into_iter().zip(return_values.into_iter()) {
             let name = parameter.variable.name;
-            let type_ = parameter.type_;
+
+            // Check register type == return value type.
+            let register_type = parameter.type_;
+            let return_value_type = value.to_type(&span)?;
+
+            if !register_type.eq_flat(&return_value_type) {
+                return Err(OutputBytesError::mismatched_output_types(
+                    register_type,
+                    return_value_type,
+                    span,
+                ));
+            }
+
             let value = value.to_string();
 
-            let format = format!("{}: {} = {};\n", name, type_, value,);
+            let format = format!("{}: {} = {};\n", name, register_type, value,);
 
             string.push_str(&format);
         }
diff --git a/compiler/tests/input_files/mod.rs b/compiler/tests/input_files/mod.rs
index ddfd9aa108..49eba0b9bc 100644
--- a/compiler/tests/input_files/mod.rs
+++ b/compiler/tests/input_files/mod.rs
@@ -16,4 +16,5 @@
 
 mod program_input;
 mod program_input_and_program_state;
+mod program_registers;
 mod program_state;
diff --git a/compiler/tests/input_files/program_registers/input/array.in b/compiler/tests/input_files/program_registers/input/array.in
new file mode 100644
index 0000000000..a952dda5a6
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/input/array.in
@@ -0,0 +1,2 @@
+[registers]
+r2: [[u8; 4]; 2] = [[0u64, 0u64, 0u64, 0u64], [0u64, 0u64, 0u64, 0u64]];
\ No newline at end of file
diff --git a/compiler/tests/input_files/program_registers/input/main.in b/compiler/tests/input_files/program_registers/input/main.in
new file mode 100644
index 0000000000..1bff5e584f
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/input/main.in
@@ -0,0 +1,4 @@
+[main]
+
+[registers]
+r: u8 = 0u8;
\ No newline at end of file
diff --git a/compiler/tests/input_files/program_registers/mod.rs b/compiler/tests/input_files/program_registers/mod.rs
new file mode 100644
index 0000000000..894f24b810
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/mod.rs
@@ -0,0 +1,53 @@
+// Copyright (C) 2019-2020 Aleo Systems Inc.
+// This file is part of the Leo library.
+
+// The Leo library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// The Leo library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with the Leo library. If not, see <https://www.gnu.org/licenses/>.
+
+use crate::{expect_compiler_error, get_output, parse_program_with_input};
+
+#[test]
+fn test_registers_pass() {
+    let program_string = include_str!("registers_pass.leo");
+    let input_string = include_str!("input/main.in");
+    let expected = include_bytes!("output/registers_pass.out");
+
+    let program = parse_program_with_input(program_string, input_string).unwrap();
+
+    let actual = get_output(program);
+
+    assert!(expected.eq(actual.bytes().as_slice()));
+}
+
+#[test]
+fn test_registers_fail() {
+    let program_string = include_str!("registers_fail.leo");
+    let input_string = include_str!("input/main.in");
+
+    let program = parse_program_with_input(program_string, input_string).unwrap();
+
+    expect_compiler_error(program);
+}
+
+#[test]
+fn test_registers_array() {
+    let program_string = include_str!("registers_array.leo");
+    let input_string = include_str!("input/array.in");
+    let expected = include_bytes!("output/registers_array.out");
+
+    let program = parse_program_with_input(program_string, input_string).unwrap();
+
+    let actual = get_output(program);
+
+    assert!(expected.eq(actual.bytes().as_slice()));
+}
diff --git a/compiler/tests/input_files/program_registers/output/registers_array.out b/compiler/tests/input_files/program_registers/output/registers_array.out
new file mode 100644
index 0000000000..20294ac107
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/output/registers_array.out
@@ -0,0 +1,2 @@
+[registers]
+r2: [[u8; 4]; 2] = [[1, 2, 3, 4], [5, 6, 7, 8]];
diff --git a/compiler/tests/input_files/program_registers/output/registers_pass.out b/compiler/tests/input_files/program_registers/output/registers_pass.out
new file mode 100644
index 0000000000..e26ba9195e
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/output/registers_pass.out
@@ -0,0 +1,2 @@
+[registers]
+r: u8 = 1;
diff --git a/compiler/tests/input_files/program_registers/registers_array.leo b/compiler/tests/input_files/program_registers/registers_array.leo
new file mode 100644
index 0000000000..708fa0ea61
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/registers_array.leo
@@ -0,0 +1,3 @@
+function main () -> [[u8; 4]; 2] {
+    return [[1u8, 2u8, 3u8, 4u8], [5u8, 6u8, 7u8, 8u8]]
+}
\ No newline at end of file
diff --git a/compiler/tests/input_files/program_registers/registers_fail.leo b/compiler/tests/input_files/program_registers/registers_fail.leo
new file mode 100644
index 0000000000..221958dbd9
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/registers_fail.leo
@@ -0,0 +1,3 @@
+function main() -> bool {
+    return false
+}
\ No newline at end of file
diff --git a/compiler/tests/input_files/program_registers/registers_pass.leo b/compiler/tests/input_files/program_registers/registers_pass.leo
new file mode 100644
index 0000000000..ce0dbcb130
--- /dev/null
+++ b/compiler/tests/input_files/program_registers/registers_pass.leo
@@ -0,0 +1,3 @@
+function main() -> u8 {
+    return 1u8
+}
\ No newline at end of file