diff --git a/crates/smoketests/tests/smoketests/column_defaults.rs b/crates/smoketests/tests/smoketests/column_defaults.rs
new file mode 100644
index 00000000000..fb4bcb6d2e2
--- /dev/null
+++ b/crates/smoketests/tests/smoketests/column_defaults.rs
@@ -0,0 +1,311 @@
+use spacetimedb_smoketests::{
+    random_string, require_dotnet, require_emscripten, require_pnpm, ModuleLanguage, Smoketest,
+};
+
+const EXPECTED_DEFAULTS: &[(&str, &str)] = &[
+    ("bool_value", "true"),
+    ("u8_value", "8"),
+    // TODO: uncomment this once negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("i8_value", "-8"),
+    ("u16_value", "16"),
+    // TODO: uncomment this once negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("i16_value", "-16"),
+    ("u32_value", "32"),
+    // TODO: uncomment this once negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("i32_value", "-32"),
+
+    // TODO: uncomment once u64s are fixed.
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5623
+    //("u64_value", "64"),
+
+    // TODO: uncomment this once negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("i64_value", "-64"),
+
+    // TODO: uncomment once floats are fixed in C# and f32s are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5624
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5627
+    //("f32_positive_value", "32.5"),
+
+    // TODO: uncomment once floats are fixed in C#, f32s are fixed in Rust, and negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5624
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5627
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("f32_negative_value", "-32.5"),
+    ("f64_positive_value", "64.25"),
+    // TODO: uncomment once negative defaults are fixed in Rust
+    // https://github.com/clockworklabs/SpacetimeDB/issues/5622
+    //("f64_negative_value", "-64.25"),
+
+    // TODO: uncomment this once string default values are fixed in Rust
+    //("string_value", r#""default string""#),
+];
+
+fn test_defaults(test: &mut Smoketest, publish_updated: impl FnOnce(&mut Smoketest)) {
+    test.sql("INSERT INTO defaults_test_table (id) VALUES (1)").unwrap();
+    publish_updated(test);
+
+    for &(column, expected) in EXPECTED_DEFAULTS {
+        let output = test
+            .sql(&format!("SELECT {column} FROM defaults_test_table WHERE id = 1"))
+            .unwrap();
+        let actual = output.lines().last().unwrap().trim();
+        assert_eq!(actual, expected, "incorrect default for column {column}");
+    }
+}
+
+fn test_source_defaults(language: ModuleLanguage, project_name: &str, initial: &str, updated: &str) {
+    let mut test = Smoketest::builder().autopublish(false).build();
+    let database_name = format!("column-defaults-{project_name}-{}", random_string());
+    let initial_project_name = format!("{project_name}-initial");
+    let updated_project_name = format!("{project_name}-updated");
+    test.publish()
+        .name(&database_name)
+        .source(language, &initial_project_name, initial)
+        .run()
+        .unwrap();
+
+    test_defaults(&mut test, |test| {
+        test.publish()
+            .current_database()
+            .unwrap()
+            .break_clients(true)
+            .source(language, &updated_project_name, updated)
+            .run()
+            .unwrap();
+    });
+}
+
+#[test]
+fn test_rust_column_defaults() {
+    let mut test = Smoketest::builder().module_code(RUST_INITIAL).build();
+    test_defaults(&mut test, |test| {
+        test.write_module_code(RUST_UPDATED).unwrap();
+        test.publish()
+            .current_database()
+            .unwrap()
+            .break_clients(true)
+            .run()
+            .unwrap();
+    });
+}
+
+#[test]
+fn test_typescript_column_defaults() {
+    require_pnpm!();
+    test_source_defaults(
+        ModuleLanguage::TypeScript,
+        "column-defaults-ts",
+        TYPESCRIPT_INITIAL,
+        TYPESCRIPT_UPDATED,
+    );
+}
+
+#[test]
+fn test_csharp_column_defaults() {
+    require_dotnet!();
+    test_source_defaults(
+        ModuleLanguage::CSharp,
+        "column-defaults-csharp",
+        CSHARP_INITIAL,
+        CSHARP_UPDATED,
+    );
+}
+
+#[test]
+fn test_cpp_column_defaults() {
+    require_emscripten!();
+    test_source_defaults(ModuleLanguage::Cpp, "column-defaults-cpp", CPP_INITIAL, CPP_UPDATED);
+}
+
+const RUST_INITIAL: &str = r#"
+#[spacetimedb::table(accessor = defaults_test_table, public)]
+pub struct DefaultsTestTable {
+    pub id: u32,
+}
+"#;
+
+const RUST_UPDATED: &str = r#"
+#[spacetimedb::table(accessor = defaults_test_table, public)]
+pub struct DefaultsTestTable {
+    pub id: u32,
+    #[default(true)]
+    pub bool_value: bool,
+//    #[default(-8)]
+//    pub i8_value: i8,
+    #[default(8)]
+    pub u8_value: u8,
+//    #[default(-16)]
+//    pub i16_value: i16,
+    #[default(16)]
+    pub u16_value: u16,
+//    #[default(-32)]
+//    pub i32_value: i32,
+    #[default(32)]
+    pub u32_value: u32,
+//    #[default(-64)]
+//    pub i64_value: i64,
+//    #[default(64)]
+//    pub u64_value: u64,
+    #[default(32.5)]
+    pub f32_positive_value: f32,
+//    #[default(-32.5)]
+//    pub f32_negative_value: f32,
+    #[default(64.25)]
+    pub f64_positive_value: f64,
+//    #[default(-64.25)]
+//    pub f64_negative_value: f64,
+//    #[default("default string")]
+//    pub string_value: String,
+}
+"#;
+
+const TYPESCRIPT_INITIAL: &str = r#"
+import { schema, t, table } from "spacetimedb/server";
+
+const defaultsTestTable = table(
+  { name: "defaults_test_table", public: true },
+  { id: t.u32() }
+);
+
+export default schema({ defaultsTestTable });
+"#;
+
+const TYPESCRIPT_UPDATED: &str = r#"
+import { schema, t, table } from "spacetimedb/server";
+
+const defaultsTestTable = table(
+  { name: "defaults_test_table", public: true },
+  {
+    id: t.u32(),
+    bool_value: t.bool().default(true),
+    i8_value: t.i8().default(-8),
+    u8_value: t.u8().default(8),
+    i16_value: t.i16().default(-16),
+    u16_value: t.u16().default(16),
+    i32_value: t.i32().default(-32),
+    u32_value: t.u32().default(32),
+    i64_value: t.i64().default(-64n),
+    u64_value: t.u64().default(64n),
+    f32_positive_value: t.f32().default(32.5),
+    f32_negative_value: t.f32().default(-32.5),
+    f64_positive_value: t.f64().default(64.25),
+    f64_negative_value: t.f64().default(-64.25),
+    string_value: t.string().default("default string"),
+  }
+);
+
+export default schema({ defaultsTestTable });
+"#;
+
+const CSHARP_INITIAL: &str = r#"
+using SpacetimeDB;
+
+public static partial class Module
+{
+    [Table(Accessor = "defaults_test_table", Public = true)]
+    public partial struct DefaultsTestTable
+    {
+        public uint id;
+    }
+}
+"#;
+
+const CSHARP_UPDATED: &str = r#"
+using SpacetimeDB;
+
+public static partial class Module
+{
+    [Table(Accessor = "defaults_test_table", Public = true)]
+    public partial struct DefaultsTestTable
+    {
+        public uint id;
+        [Default(true)] public bool bool_value;
+        [Default((sbyte)-8)] public sbyte i8_value;
+        [Default((byte)8)] public byte u8_value;
+        [Default((short)-16)] public short i16_value;
+        [Default((ushort)16)] public ushort u16_value;
+        [Default(-32)] public int i32_value;
+        [Default(32U)] public uint u32_value;
+        [Default(-64L)] public long i64_value;
+        [Default(64UL)] public ulong u64_value;
+        //[Default(32.5f)] public float f32_positive_value;
+        //[Default(-32.5f)] public float f32_negative_value;
+        [Default(64.25)] public double f64_positive_value;
+        [Default(-64.25)] public double f64_negative_value;
+        [Default("default string")] public string string_value;
+    }
+}
+"#;
+
+const CPP_INITIAL: &str = r#"
+#include "spacetimedb.h"
+
+using namespace SpacetimeDB;
+
+struct DefaultsTestTable {
+    uint32_t id;
+};
+SPACETIMEDB_STRUCT(DefaultsTestTable, id)
+SPACETIMEDB_TABLE(DefaultsTestTable, defaults_test_table, Public)
+"#;
+
+const CPP_UPDATED: &str = r#"
+#include "spacetimedb.h"
+
+using namespace SpacetimeDB;
+
+struct DefaultsTestTable {
+    uint32_t id;
+    bool bool_value;
+    int8_t i8_value;
+    uint8_t u8_value;
+    int16_t i16_value;
+    uint16_t u16_value;
+    int32_t i32_value;
+    uint32_t u32_value;
+    int64_t i64_value;
+    uint64_t u64_value;
+    float f32_positive_value;
+    float f32_negative_value;
+    double f64_positive_value;
+    double f64_negative_value;
+    std::string string_value;
+};
+SPACETIMEDB_STRUCT(
+    DefaultsTestTable,
+    id,
+    bool_value,
+    i8_value,
+    u8_value,
+    i16_value,
+    u16_value,
+    i32_value,
+    u32_value,
+    i64_value,
+    u64_value,
+    f32_positive_value,
+    f32_negative_value,
+    f64_positive_value,
+    f64_negative_value,
+    string_value
+)
+SPACETIMEDB_TABLE(DefaultsTestTable, defaults_test_table, Public)
+FIELD_Default(defaults_test_table, bool_value, true)
+FIELD_Default(defaults_test_table, i8_value, int8_t(-8))
+FIELD_Default(defaults_test_table, u8_value, uint8_t(8))
+FIELD_Default(defaults_test_table, i16_value, int16_t(-16))
+FIELD_Default(defaults_test_table, u16_value, uint16_t(16))
+FIELD_Default(defaults_test_table, i32_value, int32_t(-32))
+FIELD_Default(defaults_test_table, u32_value, uint32_t(32))
+FIELD_Default(defaults_test_table, i64_value, int64_t(-64))
+FIELD_Default(defaults_test_table, u64_value, uint64_t(64))
+FIELD_Default(defaults_test_table, f32_positive_value, float(32.5))
+FIELD_Default(defaults_test_table, f32_negative_value, float(-32.5))
+FIELD_Default(defaults_test_table, f64_positive_value, double(64.25))
+FIELD_Default(defaults_test_table, f64_negative_value, double(-64.25))
+FIELD_Default(defaults_test_table, string_value, std::string("default string"))
+"#;
diff --git a/crates/smoketests/tests/smoketests/mod.rs b/crates/smoketests/tests/smoketests/mod.rs
index f0114e19df5..5831b4813fa 100644
--- a/crates/smoketests/tests/smoketests/mod.rs
+++ b/crates/smoketests/tests/smoketests/mod.rs
@@ -6,6 +6,7 @@ mod call;
 mod change_host_type;
 mod cli;
 mod client_connection_errors;
+mod column_defaults;
 mod confirmed_reads;
 mod connect_disconnect_from_cli;
 mod create_project;