diff --git a/Cargo.lock b/Cargo.lock
index d91d84fa0a8..67eda682304 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3541,7 +3541,7 @@ checksum = "42a4d50cdb458045afc8131fd91b64904da29548bcb63c7236e0844936c13078"
 [[package]]
 name = "temporal_rs"
 version = "0.0.4"
-source = "git+https://github.com/boa-dev/temporal.git?rev=8b796edec18a2652af282735aab4a2d0512b9a1d#8b796edec18a2652af282735aab4a2d0512b9a1d"
+source = "git+https://github.com/boa-dev/temporal.git?rev=436b07d9b27e3e2274905c9a4eabf8bbff9ad9ec#436b07d9b27e3e2274905c9a4eabf8bbff9ad9ec"
 dependencies = [
  "bitflags 2.6.0",
  "combine",
@@ -3554,6 +3554,7 @@ dependencies = [
  "tinystr 0.8.0",
  "tzif",
  "web-time",
+ "writeable 0.6.0",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index b411f795297..951f1f0f9a6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -112,7 +112,7 @@ intrusive-collections = "0.9.7"
 cfg-if = "1.0.0"
 either = "1.13.0"
 sys-locale = "0.3.2"
-temporal_rs = { git = "https://github.com/boa-dev/temporal.git", rev = "8b796edec18a2652af282735aab4a2d0512b9a1d", features = ["tzdb", "now"] }
+temporal_rs = { git = "https://github.com/boa-dev/temporal.git", rev = "436b07d9b27e3e2274905c9a4eabf8bbff9ad9ec", features = ["tzdb"] }
 web-time = "1.1.0"
 criterion = "0.5.1"
 float-cmp = "0.10.0"
diff --git a/core/engine/src/builtins/temporal/instant/mod.rs b/core/engine/src/builtins/temporal/instant/mod.rs
index 366fe7bcfe9..5177673d17a 100644
--- a/core/engine/src/builtins/temporal/instant/mod.rs
+++ b/core/engine/src/builtins/temporal/instant/mod.rs
@@ -531,10 +531,8 @@ fn to_temporal_instant(item: &JsValue, context: &mut Context) -> JsResult<InnerI
         // d. Set item to ? ToPrimitive(item, string).
         if let Some(instant) = obj.downcast_ref::<Instant>() {
             return Ok(instant.inner);
-        } else if let Some(_zdt) = obj.downcast_ref::<ZonedDateTime>() {
-            return Err(JsNativeError::error()
-                .with_message("Not yet implemented.")
-                .into());
+        } else if let Some(zdt) = obj.downcast_ref::<ZonedDateTime>() {
+            return Ok(zdt.inner.to_instant());
         }
         item.to_primitive(context, PreferredType::String)?
     } else {
diff --git a/core/engine/src/builtins/temporal/options.rs b/core/engine/src/builtins/temporal/options.rs
index 46883c52eeb..3213435bbab 100644
--- a/core/engine/src/builtins/temporal/options.rs
+++ b/core/engine/src/builtins/temporal/options.rs
@@ -13,7 +13,7 @@ use crate::{
     js_string, Context, JsNativeError, JsObject, JsResult, JsString, JsValue,
 };
 use temporal_rs::options::{
-    ArithmeticOverflow, CalendarName, DifferenceSettings, Disambiguation, DurationOverflow,
+    ArithmeticOverflow, DifferenceSettings, Disambiguation, DisplayCalendar, DurationOverflow,
     OffsetDisambiguation, RoundingIncrement, TemporalRoundingMode, TemporalUnit,
 };
 
@@ -116,7 +116,7 @@ impl ParsableOptionType for DurationOverflow {}
 impl ParsableOptionType for Disambiguation {}
 impl ParsableOptionType for OffsetDisambiguation {}
 impl ParsableOptionType for TemporalRoundingMode {}
-impl ParsableOptionType for CalendarName {}
+impl ParsableOptionType for DisplayCalendar {}
 
 impl OptionType for RoundingIncrement {
     fn from_value(value: JsValue, context: &mut Context) -> JsResult<Self> {
diff --git a/core/engine/src/builtins/temporal/plain_date/mod.rs b/core/engine/src/builtins/temporal/plain_date/mod.rs
index a173a320c74..a008fb98217 100644
--- a/core/engine/src/builtins/temporal/plain_date/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_date/mod.rs
@@ -20,7 +20,9 @@ use crate::{
 use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
 use temporal_rs::{
-    options::ArithmeticOverflow, partial::PartialDate, PlainDate as InnerDate, TinyAsciiStr,
+    options::{ArithmeticOverflow, DisplayCalendar},
+    partial::PartialDate,
+    PlainDate as InnerDate, TinyAsciiStr,
 };
 
 use super::{
@@ -214,6 +216,8 @@ impl IntrinsicObject for PlainDate {
             .method(Self::since, js_string!("since"), 1)
             .method(Self::equals, js_string!("equals"), 1)
             .method(Self::to_plain_datetime, js_string!("toPlainDateTime"), 0)
+            .method(Self::to_string, js_string!("toString"), 0)
+            .method(Self::to_json, js_string!("toJSON"), 0)
             .method(Self::value_of, js_string!("valueOf"), 0)
             .build();
     }
@@ -730,6 +734,35 @@ impl PlainDate {
         create_temporal_datetime(date.inner.to_date_time(time)?, None, context).map(Into::into)
     }
 
+    /// 3.3.30 `Temporal.PlainDate.prototype.toString ( [ options ] )`
+    fn to_string(this: &JsValue, args: &[JsValue], context: &mut Context) -> JsResult<JsValue> {
+        let date = this
+            .as_object()
+            .and_then(JsObject::downcast_ref::<Self>)
+            .ok_or_else(|| {
+                JsNativeError::typ().with_message("the this object must be a PlainDate object.")
+            })?;
+
+        let options = get_options_object(args.get_or_undefined(0))?;
+        let display_calendar =
+            get_option::<DisplayCalendar>(&options, js_string!("calendarName"), context)?
+                .unwrap_or(DisplayCalendar::Auto);
+        Ok(JsString::from(date.inner.to_ixdtf_string(display_calendar)).into())
+    }
+
+    // 3.3.32 `Temporal.PlainDate.prototype.toJSON ( )`
+    fn to_json(this: &JsValue, _: &[JsValue], _: &mut Context) -> JsResult<JsValue> {
+        let date = this
+            .as_object()
+            .and_then(JsObject::downcast_ref::<Self>)
+            .ok_or_else(|| {
+                JsNativeError::typ().with_message("the this object must be a PlainDate object.")
+            })?;
+
+        Ok(JsString::from(date.inner.to_string()).into())
+    }
+
+    /// 3.3.33 `Temporal.PlainDate.prototype.valueOf ( )`
     pub(crate) fn value_of(_this: &JsValue, _: &[JsValue], _: &mut Context) -> JsResult<JsValue> {
         Err(JsNativeError::typ()
             .with_message("`valueOf` not supported by Temporal built-ins. See 'compare', 'equals', or `toString`")
diff --git a/core/engine/src/builtins/temporal/plain_date/tests.rs b/core/engine/src/builtins/temporal/plain_date/tests.rs
index d98f5313e89..f492a3d61c1 100644
--- a/core/engine/src/builtins/temporal/plain_date/tests.rs
+++ b/core/engine/src/builtins/temporal/plain_date/tests.rs
@@ -41,6 +41,6 @@ fn string_null_option_value() {
     run_test_actions([TestAction::assert_native_error(
         "Temporal.PlainDate.from('1976-11-18Z', null)",
         JsNativeErrorKind::Range,
-        "Error: Unexpected character found after parsing was completed.",
+        "RangeError: Unexpected character found after parsing was completed.",
     )]);
 }
diff --git a/core/engine/src/builtins/temporal/plain_month_day/mod.rs b/core/engine/src/builtins/temporal/plain_month_day/mod.rs
index 26f20b203b0..8030d1cf07a 100644
--- a/core/engine/src/builtins/temporal/plain_month_day/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_month_day/mod.rs
@@ -20,7 +20,7 @@ use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
 
 use temporal_rs::{
-    options::{ArithmeticOverflow, CalendarName},
+    options::{ArithmeticOverflow, DisplayCalendar},
     partial::PartialDate,
     PlainMonthDay as InnerMonthDay, TinyAsciiStr,
 };
@@ -110,8 +110,8 @@ impl PlainMonthDay {
         // 4. Let showCalendar be ? ToShowCalendarOption(options).
         // Get calendarName from the options object
         let show_calendar =
-            get_option::<CalendarName>(&options, js_string!("calendarName"), context)?
-                .unwrap_or(CalendarName::Auto);
+            get_option::<DisplayCalendar>(&options, js_string!("calendarName"), context)?
+                .unwrap_or(DisplayCalendar::Auto);
 
         Ok(month_day_to_string(inner, show_calendar))
     }
@@ -231,7 +231,7 @@ impl BuiltInConstructor for PlainMonthDay {
 
 // ==== `PlainMonthDay` Abstract Operations ====
 
-fn month_day_to_string(inner: &InnerMonthDay, show_calendar: CalendarName) -> JsValue {
+fn month_day_to_string(inner: &InnerMonthDay, show_calendar: DisplayCalendar) -> JsValue {
     // Let month be monthDay.[[ISOMonth]] formatted as a two-digit decimal number, padded to the left with a zero if necessary
     let month = inner.iso_month().to_string();
 
@@ -252,11 +252,11 @@ fn month_day_to_string(inner: &InnerMonthDay, show_calendar: CalendarName) -> Js
     //     b. Set result to the string-concatenation of result, the code unit 0x0040 (COMMERCIAL AT), and calendarString.
     if (matches!(
         show_calendar,
-        CalendarName::Critical | CalendarName::Always | CalendarName::Auto
-    )) && !(matches!(show_calendar, CalendarName::Auto) && calendar_id == "iso8601")
+        DisplayCalendar::Critical | DisplayCalendar::Always | DisplayCalendar::Auto
+    )) && !(matches!(show_calendar, DisplayCalendar::Auto) && calendar_id == "iso8601")
     {
         let year = inner.iso_year().to_string();
-        let flag = if matches!(show_calendar, CalendarName::Critical) {
+        let flag = if matches!(show_calendar, DisplayCalendar::Critical) {
             "!"
         } else {
             ""
diff --git a/core/engine/src/builtins/temporal/plain_year_month/mod.rs b/core/engine/src/builtins/temporal/plain_year_month/mod.rs
index 389858c044b..b06cbfa1403 100644
--- a/core/engine/src/builtins/temporal/plain_year_month/mod.rs
+++ b/core/engine/src/builtins/temporal/plain_year_month/mod.rs
@@ -20,7 +20,7 @@ use boa_gc::{Finalize, Trace};
 use boa_profiler::Profiler;
 
 use temporal_rs::{
-    options::{ArithmeticOverflow, CalendarName},
+    options::{ArithmeticOverflow, DisplayCalendar},
     Duration, PlainYearMonth as InnerYearMonth,
 };
 
@@ -433,8 +433,8 @@ impl PlainYearMonth {
         // 4. Let showCalendar be ? ToShowCalendarOption(options).
         // Get calendarName from the options object
         let show_calendar =
-            get_option::<CalendarName>(&options, js_string!("calendarName"), context)?
-                .unwrap_or(CalendarName::Auto);
+            get_option::<DisplayCalendar>(&options, js_string!("calendarName"), context)?
+                .unwrap_or(DisplayCalendar::Auto);
 
         Ok(year_month_to_string(inner, show_calendar))
     }
@@ -529,7 +529,7 @@ fn add_or_subtract_duration(
     create_temporal_year_month(year_month_result, None, context)
 }
 
-fn year_month_to_string(inner: &InnerYearMonth, show_calendar: CalendarName) -> JsValue {
+fn year_month_to_string(inner: &InnerYearMonth, show_calendar: DisplayCalendar) -> JsValue {
     // Let year be PadISOYear(yearMonth.[[ISOYear]]).
     let year = inner.padded_iso_year_string();
     // Let month be ToZeroPaddedDecimalString(yearMonth.[[ISOMonth]], 2).
@@ -545,12 +545,12 @@ fn year_month_to_string(inner: &InnerYearMonth, show_calendar: CalendarName) ->
     // 7. Set result to the string-concatenation of result and calendarString.
     if matches!(
         show_calendar,
-        CalendarName::Critical | CalendarName::Always | CalendarName::Auto
-    ) && !(matches!(show_calendar, CalendarName::Auto) && inner.calendar_id() == "iso8601")
+        DisplayCalendar::Critical | DisplayCalendar::Always | DisplayCalendar::Auto
+    ) && !(matches!(show_calendar, DisplayCalendar::Auto) && inner.calendar_id() == "iso8601")
     {
         let calendar = inner.calendar_id();
         let calendar_string = calendar.to_string();
-        let flag = if matches!(show_calendar, CalendarName::Critical) {
+        let flag = if matches!(show_calendar, DisplayCalendar::Critical) {
             "!"
         } else {
             ""