diff --git a/crates/bashkit/docs/compatibility.md b/crates/bashkit/docs/compatibility.md
index 638699618..333eda947 100644
--- a/crates/bashkit/docs/compatibility.md
+++ b/crates/bashkit/docs/compatibility.md
@@ -91,7 +91,7 @@ for sandbox security reasons. See the compliance spec for details.
 | `uniq` | `-c`, `-d`, `-u` | Filter duplicate lines |
 | `cut` | `-d DELIM`, `-f FIELDS` | Extract fields |
 | `tr` | `-d`, character ranges | Translate/delete chars |
-| `date` | `+FORMAT`, `-u`, `-R`, `-I`, `-r`, `-d`/`--date` (relative, compound, epoch) | Display/format date with sandboxed IANA timezone support |
+| `date` | `+FORMAT`, `-u`, `-R`, `-I`, `-r`, `-d`/`--date` (relative, compound, epoch, ISO date-times with optional seconds and zone) | Display/format date with sandboxed IANA timezone support |
 | `wait` | `[-n] [-p VAR] [-f] [ID...]` (PID or `%jobspec`) | Wait for background jobs |
 | `jobs` | `-l`, `-p` | List running background jobs |
 | `ps` | `-f`, `aux`, `-o`, `-p` | Virtual process list (shell + jobs) |
diff --git a/crates/bashkit/src/builtins/date.rs b/crates/bashkit/src/builtins/date.rs
index 35aca11a1..b395583c8 100644
--- a/crates/bashkit/src/builtins/date.rs
+++ b/crates/bashkit/src/builtins/date.rs
@@ -307,18 +307,43 @@ fn parse_base_date(
             .ok_or_else(|| format!("date out of range: '{}'", s));
     }
 
-    // Try ISO-like formats: YYYY-MM-DD HH:MM:SS, YYYY-MM-DD
-    if let Ok(dt) = NaiveDateTime::parse_from_str(s, "%Y-%m-%d %H:%M:%S") {
-        return timezone.local_to_utc(dt, s);
-    }
-    if let Ok(dt) = NaiveDateTime::parse_from_str(s, "%Y-%m-%dT%H:%M:%S") {
-        return timezone.local_to_utc(dt, s);
+    // Try ISO-like formats: YYYY-MM-DD, optionally with [ T]HH:MM[:SS[.frac]],
+    // read in the sandbox TZ unless followed by UTC/GMT, Z or a numeric offset
+    // (git's %ci)
+    const ISO: [&str; 4] = [
+        "%Y-%m-%d %H:%M:%S%.f",
+        "%Y-%m-%dT%H:%M:%S%.f",
+        "%Y-%m-%d %H:%M",
+        "%Y-%m-%dT%H:%M",
+    ];
+    let (wall, utc) = match s.rsplit_once(' ') {
+        Some((wall, zone))
+            if zone.eq_ignore_ascii_case("utc") || zone.eq_ignore_ascii_case("gmt") =>
+        {
+            (wall, true)
+        }
+        _ => (s, false),
+    };
+    let naive = ISO
+        .iter()
+        .find_map(|f| NaiveDateTime::parse_from_str(wall, f).ok())
+        .or_else(|| {
+            NaiveDate::parse_from_str(wall, "%Y-%m-%d")
+                .ok()?
+                .and_hms_opt(0, 0, 0)
+        });
+    if let Some(dt) = naive {
+        return if utc {
+            Ok(dt.and_utc())
+        } else {
+            timezone.local_to_utc(dt, s)
+        };
     }
-    if let Ok(d) = NaiveDate::parse_from_str(s, "%Y-%m-%d") {
-        let dt = d
-            .and_hms_opt(0, 0, 0)
-            .ok_or_else(|| format!("invalid date '{}'", s))?;
-        return timezone.local_to_utc(dt, s);
+    if let Some(dt) = ISO
+        .iter()
+        .find_map(|f| DateTime::parse_from_str(s, &format!("{f} %#z")).ok())
+    {
+        return Ok(dt.with_timezone(&Utc));
     }
 
     // Try "Mon DD, YYYY" format
@@ -355,7 +380,7 @@ fn parse_base_date(
 /// Supports simple expressions:
 ///   "now", "yesterday", "tomorrow", "N days ago", "+N days",
 ///   "N weeks ago", "N months ago", "N years ago", "N hours ago",
-///   "@EPOCH", "YYYY-MM-DD", "YYYY-MM-DD HH:MM:SS"
+///   "@EPOCH", "YYYY-MM-DD[ HH:MM[:SS[.frac]]][ UTC|+HHMM]"
 ///
 /// Supports compound expressions (base ± modifier):
 ///   "2024-01-15 + 30 days", "yesterday - 2 hours",
@@ -990,6 +1015,41 @@ mod tests {
         assert!(result.stderr.contains("invalid date"));
     }
 
+    /// Expected values match GNU date 9.12.
+    #[tokio::test]
+    async fn test_date_d_iso_times_and_zones() {
+        for (input, expected) in [
+            ("2026-10-08 14:30", "2026-10-08 14:30:00.000000000"),
+            ("2026-10-08T14:30", "2026-10-08 14:30:00.000000000"),
+            ("2026-10-08 14:30:15.25", "2026-10-08 14:30:15.250000000"),
+            ("2026-10-08 14:30 UTC", "2026-10-08 14:30:00.000000000"),
+            ("2026-10-08 14:30:15 gmt", "2026-10-08 14:30:15.000000000"),
+            ("2026-10-08T14:30Z", "2026-10-08 14:30:00.000000000"),
+            ("2026-10-08 14:30:15 +0200", "2026-10-08 12:30:15.000000000"),
+            ("2026-10-08 14:30:15+02:00", "2026-10-08 12:30:15.000000000"),
+            ("2026-10-08 14:30:15 -05", "2026-10-08 19:30:15.000000000"),
+            ("2026-10-08 UTC", "2026-10-08 00:00:00.000000000"),
+        ] {
+            let result = run_date(&["-u", "-d", input, "+%F %T.%N"]).await;
+            assert_eq!(result.stdout.trim(), expected, "{input}");
+        }
+    }
+
+    #[tokio::test]
+    async fn test_date_d_iso_invalid_fields() {
+        for input in [
+            "2026-02-30 10:00",
+            "2026-10-08 24:00",
+            "2026-10-08 12:60",
+            "2026-10-08 -05",
+            "2026-10-08 14:30 +2500",
+        ] {
+            let result = run_date(&["-d", input]).await;
+            assert_eq!(result.exit_code, 1, "{input}");
+            assert!(result.stderr.contains("invalid date"), "{input}");
+        }
+    }
+
     #[tokio::test]
     async fn test_date_d_relative_weeks() {
         let result = run_date(&["-d", "2 weeks ago", "+%Y-%m-%d"]).await;
diff --git a/crates/bashkit/tests/integration/date_timezone_differential_tests.rs b/crates/bashkit/tests/integration/date_timezone_differential_tests.rs
index 72b8d2a61..c281100f1 100644
--- a/crates/bashkit/tests/integration/date_timezone_differential_tests.rs
+++ b/crates/bashkit/tests/integration/date_timezone_differential_tests.rs
@@ -70,6 +70,18 @@ async fn matches_gnu_date_for_timezone_sensitive_inputs() {
             "America/Chicago",
             &["-u", "-d", "2024-01-15T10:40:00-06:00", "+%s %T %Z %z"],
         ),
+        (
+            "America/Chicago",
+            &["-d", "2024-07-15 10:40", "+%s %F %T %Z %z"],
+        ),
+        (
+            "America/Chicago",
+            &["-d", "2024-07-15 10:40:00 UTC", "+%s %F %T %Z %z"],
+        ),
+        (
+            "America/Chicago",
+            &["-d", "2024-07-15 10:40:00.5 +0200", "+%s %N %F %T %Z %z"],
+        ),
         ("Etc/GMT+6", &["-d", "@0", "+%F %T %Z %z"]),
         ("UTC", &["-d", "@0", "+%C %G %g %u %V %3N %6N %N"]),
     ] {
diff --git a/crates/bashkit/tests/integration/date_timezone_tests.rs b/crates/bashkit/tests/integration/date_timezone_tests.rs
index 50db4a8fb..8a3b46a81 100644
--- a/crates/bashkit/tests/integration/date_timezone_tests.rs
+++ b/crates/bashkit/tests/integration/date_timezone_tests.rs
@@ -150,3 +150,61 @@ async fn gnu_nanosecond_precision_uses_validated_formatter() {
     assert_eq!(result.exit_code, 0, "{}", result.stderr);
     assert_eq!(result.stdout.trim(), "000 000000 000000000");
 }
+
+#[tokio::test]
+async fn shared_iso_date_parsing_preserves_instants_across_builtins() {
+    for (input, expected) in [
+        ("2024-01-15 10:40", "2024-01-15 16:40:00.000000000"),
+        ("2024-01-15 10:40 UTC", "2024-01-15 10:40:00.000000000"),
+        ("2024-01-15 10:40 gmt", "2024-01-15 10:40:00.000000000"),
+        ("2024-01-15T10:40Z", "2024-01-15 10:40:00.000000000"),
+        (
+            "2024-01-15 10:40:00.5 +0200",
+            "2024-01-15 08:40:00.500000000",
+        ),
+        ("2024-01-15 10:40 -05", "2024-01-15 15:40:00.000000000"),
+    ] {
+        let script = format!(
+            "date -u -d '{input}' '+%F %T.%N'; \
+             touch -d '{input}' /tmp/stamp && date -u -r /tmp/stamp '+%F %T.%N'; \
+             find /tmp/stamp -newermt '{input}'; \
+             find /tmp/stamp -newermt '{input} + 1 second'; \
+             find /tmp/stamp -newermt '{input} - 1 second'"
+        );
+        let result = fixed_date(Some("America/Chicago"), &script).await;
+        assert_eq!(result.exit_code, 0, "{input}: {}", result.stderr);
+        assert!(result.stderr.is_empty(), "{input}: {}", result.stderr);
+        assert_eq!(
+            result.stdout,
+            format!("{expected}\n{expected}\n/tmp/stamp\n"),
+            "{input}"
+        );
+    }
+}
+
+#[tokio::test]
+async fn shared_iso_date_parsing_rejects_invalid_inputs_before_file_effects() {
+    for input in [
+        "2024-03-10 02:30", // DST gap in the sandbox timezone.
+        "2024-02-30 10:40",
+        "2024-07-15 24:00",
+        "2024-07-15 10:40 +2500",
+        "2024-07-15 10:40 +0260",
+        "2024-07-15 10:40 UTC trailing",
+        "2024-07-15 10:40 /etc/localtime",
+    ] {
+        let mut bash = Bash::builder().env("TZ", "America/Chicago").build();
+        for script in [
+            format!("date -d '{input}' +%s"),
+            format!("touch -d '{input}' /tmp/rejected"),
+            format!("find /tmp -newermt '{input}'"),
+        ] {
+            let result = bash.exec(&script).await.unwrap();
+            assert_eq!(result.exit_code, 1, "{script}: {}", result.stderr);
+            assert!(result.stdout.is_empty(), "{script}: {}", result.stdout);
+            assert!(!result.stderr.is_empty(), "{script}");
+        }
+        let result = bash.exec("test -e /tmp/rejected").await.unwrap();
+        assert_eq!(result.exit_code, 1, "invalid touch created a file: {input}");
+    }
+}
diff --git a/crates/bashkit/tests/spec_cases/bash/date.test.sh b/crates/bashkit/tests/spec_cases/bash/date.test.sh
index 8c79dea58..b7c7d1c36 100644
--- a/crates/bashkit/tests/spec_cases/bash/date.test.sh
+++ b/crates/bashkit/tests/spec_cases/bash/date.test.sh
@@ -232,6 +232,23 @@ date -d '2024-06-15 - 30 days' +%Y-%m-%d
 2024-05-16
 ### end
 
+### date_iso_without_seconds
+date -u -d '2026-10-08 14:30' '+%F %T'
+### expect
+2026-10-08 14:30:00
+### end
+
+### date_iso_zone_suffix
+# Named zones, Z, and git's %ci numeric offset
+date -u -d '2026-10-08 14:30:15 UTC' '+%F %T'
+date -u -d '2026-10-08T14:30Z' '+%F %T'
+date -u -d '2026-10-08 14:30:15 +0200' '+%F %T'
+### expect
+2026-10-08 14:30:15
+2026-10-08 14:30:00
+2026-10-08 12:30:15
+### end
+
 ### date_compound_date_plus_days
 date -d '2024-01-15 + 30 days' +%Y-%m-%d
 ### expect
diff --git a/knowledge/operations/limitations.md b/knowledge/operations/limitations.md
index 5481bd635..19c466ad7 100644
--- a/knowledge/operations/limitations.md
+++ b/knowledge/operations/limitations.md
@@ -139,6 +139,18 @@ builtins are currently tracked; partial boundaries follow.
 | L-DATE-001 | date | `TZ` accepts bundled IANA identifiers/aliases only. POSIX rule strings and `:zoneinfo` paths are unsupported and intentionally resolve to UTC because the sandbox has no trusted host zoneinfo filesystem. GNU nanosecond formatting supports the useful `%N`/`%3N`/`%6N`/`%9N` forms, not other widths | `date_timezone_tests` |
 | L-MAPFILE-001 | mapfile | `-u FD` reads only fd 0, and the `-C`/`-c` callback is not run; both exit 2 with a message instead of reading the wrong input | `mapfile_bad_option` (param-expansion-gaps spec) |
 
+`date -d`, `touch -d`, and `find -newermt` share ISO date-string parsing:
+`YYYY-MM-DD` and date-times with a space or `T`, `HH:MM`, optional seconds,
+and optional fractional seconds. Naive values use the sandbox `TZ`; explicit
+`UTC`/`GMT`, `Z`, and numeric offsets (`+0200`, `+02:00`, `-05`) determine the
+instant independently of that zone. Date-only values also accept `UTC`/`GMT`.
+`date -u` changes display only. Other named input zones, comma fractions,
+date-only `Z`, and offsets outside chrono's range remain rejected. Host zoneinfo
+is never consulted. `shared_iso_date_parsing_*` tests cover shared instants,
+fractional file timestamps, strict newer-than comparisons, and rejection before
+file effects; `date_timezone_differential_tests` compares supported forms with
+GNU date when available.
+
 ### CPython runtime (`cpython` feature)
 
 Boundaries of the WebAssembly CPython guest; see