diff --git a/CHANGELOG.md b/CHANGELOG.md
index db8764d..4a68882 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,38 @@
 
 All notable changes to the OilPriceAPI Python SDK will be documented in this file.
 
+## [1.13.0] - 2026-08-23
+
+### Fixed
+
+- **`get_multiple()` now batches — up to 20 codes per request instead of one
+  request per code.** The REST API accepts 20 commodity codes in a single
+  request that counts **once** against quota, so the method whose purpose is
+  fetching several prices previously cost up to **20x more quota than writing
+  the call by hand**. Through it the free plan was 50 code-reads a day; through
+  the raw API it is 1,000.
+- The same fix is applied to `AsyncPricesResource.get_multiple()`, which was
+  worse: `asyncio.gather` fanned out one request **per code** concurrently,
+  which could also trip the 60-per-60-second rate limit on a long list. Chunks
+  are still gathered concurrently, so 25 codes cost 2 requests rather than 25.
+
+### Changed
+
+- **Your quota consumption will drop.** This is in your favour and requires no
+  code change, but it is a behaviour change: a `get_multiple()` call that
+  previously consumed N requests now consumes `ceil(N / 20)`.
+- The per-code failure contract is unchanged. Because the API rejects the whole
+  request when any code in it is unknown, a failed batch is retried per code —
+  for that chunk only — so `return_failures=True` still reports exactly which
+  code was at fault.
+
+### Documentation
+
+- Polling examples now default to an interval that fits the free plan
+  (30 minutes), with a plan/interval table and the measured update cadence of
+  the underlying data. Nothing we publish moves faster than about every
+  2.5 minutes, so a shorter timer returns the same number.
+
 ## [1.12.8] - 2026-08-12
 
 ### Fixed
diff --git a/oilpriceapi/version.py b/oilpriceapi/version.py
index 3e3d79c..f5d9dd8 100644
--- a/oilpriceapi/version.py
+++ b/oilpriceapi/version.py
@@ -5,6 +5,6 @@
 Used in __init__.py, client.py, and async_client.py.
 """
 
-__version__ = "1.12.8"
+__version__ = "1.13.0"
 SDK_VERSION = __version__
 SDK_NAME = "oilpriceapi-python"
diff --git a/pyproject.toml b/pyproject.toml
index 5e2b118..62fa9cd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "oilpriceapi"
-version = "1.12.8"
+version = "1.13.0"
 description = "Official Python SDK for source-timestamped OilPriceAPI energy data"
 authors = [
     {name = "OilPriceAPI", email = "support@oilpriceapi.com"}
diff --git a/tests/test_release_readiness.py b/tests/test_release_readiness.py
index dd12ef9..e1aa1ba 100644
--- a/tests/test_release_readiness.py
+++ b/tests/test_release_readiness.py
@@ -170,7 +170,13 @@ def test_package_version_helper_reads_the_project_version() -> None:
         capture_output=True,
         text=True,
     )
-    assert result.stdout.strip() == "1.12.8"
+    # Read the expected value from pyproject rather than hard-coding it. The
+    # helper's job is "does it report the PROJECT version", not "is the version
+    # 1.12.8" — pinning the literal made this test fail on every release for a
+    # reason unrelated to what it guards.
+    pyproject = (ROOT / "pyproject.toml").read_text()
+    expected = re.search(r'^version = "([^"]+)"', pyproject, re.M).group(1)
+    assert result.stdout.strip() == expected
 
 
 def test_every_workflow_pins_actions_and_hardens_each_checkout_step() -> None: