diff --git a/Makefile b/Makefile
index 01df3e8..228cf9a 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-all: fuzzer-binascii fuzzer-html fuzzer-email fuzzer-httpclient fuzzer-json fuzzer-difflib fuzzer-csv fuzzer-decode fuzzer-ast fuzzer-tarfile fuzzer-tarfile-hypothesis fuzzer-zipfile fuzzer-zipfile-hypothesis fuzzer-re fuzzer-configparser fuzzer-tomllib fuzzer-plistlib fuzzer-xml fuzzer-zoneinfo
+all: fuzzer-binascii fuzzer-html fuzzer-email fuzzer-httpclient fuzzer-json fuzzer-difflib fuzzer-csv fuzzer-decode fuzzer-ast fuzzer-tarfile fuzzer-tarfile-hypothesis fuzzer-zipfile fuzzer-zipfile-hypothesis fuzzer-re fuzzer-configparser fuzzer-tomllib fuzzer-plistlib fuzzer-xml fuzzer-zoneinfo fuzzer-textio
 
 PYTHON_CONFIG_PATH=$(CPYTHON_INSTALL_PATH)/bin/python3-config
 CXXFLAGS += $(shell $(PYTHON_CONFIG_PATH) --cflags)
@@ -42,3 +42,6 @@ fuzzer-xml:
 	clang++ $(CXXFLAGS) $(LIB_FUZZING_ENGINE) -std=c++17 fuzzer.cpp -DPYTHON_HARNESS_PATH="\"xml.py\"" -ldl $(LDFLAGS) -o fuzzer-xml
 fuzzer-zoneinfo:
 	clang++ $(CXXFLAGS) $(LIB_FUZZING_ENGINE) -std=c++17 fuzzer.cpp -DPYTHON_HARNESS_PATH="\"zoneinfo.py\"" -ldl $(LDFLAGS) -o fuzzer-zoneinfo
+
+fuzzer-textio:
+	clang++ $(CXXFLAGS) $(LIB_FUZZING_ENGINE) -std=c++17 fuzzer.cpp -DPYTHON_HARNESS_PATH="\"textio.py\"" -ldl $(LDFLAGS) -o fuzzer-textio
diff --git a/corp-textio/bom_only b/corp-textio/bom_only
new file mode 100644
index 0000000..9850b79
Binary files /dev/null and b/corp-textio/bom_only differ
diff --git a/corp-textio/empty_input b/corp-textio/empty_input
new file mode 100644
index 0000000..5320c68
Binary files /dev/null and b/corp-textio/empty_input differ
diff --git a/corp-textio/latin1_read b/corp-textio/latin1_read
new file mode 100644
index 0000000..f027404
Binary files /dev/null and b/corp-textio/latin1_read differ
diff --git a/corp-textio/surrogateesc b/corp-textio/surrogateesc
new file mode 100644
index 0000000..63214b0
Binary files /dev/null and b/corp-textio/surrogateesc differ
diff --git a/corp-textio/utf16_odd b/corp-textio/utf16_odd
new file mode 100644
index 0000000..254078a
Binary files /dev/null and b/corp-textio/utf16_odd differ
diff --git a/corp-textio/utf16be_read b/corp-textio/utf16be_read
new file mode 100644
index 0000000..f4ed067
Binary files /dev/null and b/corp-textio/utf16be_read differ
diff --git a/corp-textio/utf16bom_read b/corp-textio/utf16bom_read
new file mode 100644
index 0000000..2b38295
Binary files /dev/null and b/corp-textio/utf16bom_read differ
diff --git a/corp-textio/utf16le_read b/corp-textio/utf16le_read
new file mode 100644
index 0000000..35dc0ec
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diff --git a/corp-textio/utf32be_iter b/corp-textio/utf32be_iter
new file mode 100644
index 0000000..55c206c
Binary files /dev/null and b/corp-textio/utf32be_iter differ
diff --git a/corp-textio/utf32bom_read b/corp-textio/utf32bom_read
new file mode 100644
index 0000000..12cf7b9
Binary files /dev/null and b/corp-textio/utf32bom_read differ
diff --git a/corp-textio/utf32le_readn b/corp-textio/utf32le_readn
new file mode 100644
index 0000000..d5e7516
Binary files /dev/null and b/corp-textio/utf32le_readn differ
diff --git a/corp-textio/utf8_crlf_iter b/corp-textio/utf8_crlf_iter
new file mode 100644
index 0000000..bfd2aa4
Binary files /dev/null and b/corp-textio/utf8_crlf_iter differ
diff --git a/corp-textio/utf8_read b/corp-textio/utf8_read
new file mode 100644
index 0000000..032b182
Binary files /dev/null and b/corp-textio/utf8_read differ
diff --git a/corp-textio/utf8_readlines b/corp-textio/utf8_readlines
new file mode 100644
index 0000000..3453bcf
Binary files /dev/null and b/corp-textio/utf8_readlines differ
diff --git a/corp-textio/utf8_readn b/corp-textio/utf8_readn
new file mode 100644
index 0000000..8f5983c
Binary files /dev/null and b/corp-textio/utf8_readn differ
diff --git a/corp-textio/utf8_truncated b/corp-textio/utf8_truncated
new file mode 100644
index 0000000..11991c4
Binary files /dev/null and b/corp-textio/utf8_truncated differ
diff --git a/fuzz_targets.txt b/fuzz_targets.txt
index b016889..2efbc53 100644
--- a/fuzz_targets.txt
+++ b/fuzz_targets.txt
@@ -12,6 +12,7 @@ plistlib plist.py
 re re.py
 tarfile tarfile.py
 tarfile-hypothesis tarfile_hypothesis.py
+textio textio.py
 tomllib tomllib.py
 xml xml.py
 zipfile zipfile.py
diff --git a/fuzzer-textio.dict b/fuzzer-textio.dict
new file mode 100644
index 0000000..1e9ee25
--- /dev/null
+++ b/fuzzer-textio.dict
@@ -0,0 +1,29 @@
+# UTF/latin-1 decode tokens: BOMs, partial sequences, newlines, surrogates
+"\xef\xbb\xbf"
+"\xff\xfe"
+"\xfe\xff"
+"\xff\xfe\x00\x00"
+"\x00\x00\xfe\xff"
+"\xc3"
+"\xc3\xa9"
+"\xe2\x82"
+"\xe2\x82\xac"
+"\xf0\x9f"
+"\xf0\x9f\x98"
+"\xd8"
+"\xd8\x00"
+"\xdc\x8c"
+"\x00\xdc"
+"\x00\x41"
+"\x41\x00"
+"\x00\x00\x00\x41"
+"\x41\x00\x00\x00"
+"\xff"
+"\x80"
+"\x0d"
+"\x0d\x0a"
+"\x0a\x0d"
+"a\x0a"
+"\x00\x0a"
+"abc\x0d\x0a"
+"\x1a"
diff --git a/textio.py b/textio.py
new file mode 100644
index 0000000..f709d61
--- /dev/null
+++ b/textio.py
@@ -0,0 +1,57 @@
+"""Fuzz io.TextIOWrapper over untrusted bytes.
+
+The incremental decoder, readahead buffer, newline normalisation, error
+handlers and teardown paths are all C code (Modules/_io/*.c). The input
+header selects a C-implemented encoding, an error handler, a newline
+mode and a read pattern; only UnicodeDecodeError (the strict handler on
+malformed bytes) is expected -- anything else propagates as a finding.
+"""
+import io
+
+MAX_TEXTIO_TEST_SIZE = 0x100000  # 1 MiB
+
+ENCODINGS = [
+    "utf-8",
+    "utf-16",
+    "utf-16-le",
+    "utf-16-be",
+    "utf-32",
+    "utf-32-le",
+    "utf-32-be",
+    "latin-1",
+]
+ERRORS = ["strict", "replace", "ignore", "surrogateescape"]
+NEWLINES = ["", "\n", "\r", "\r\n"]
+
+
+def FuzzerRunOne(FuzzerInput):
+    if len(FuzzerInput) < 6 or len(FuzzerInput) > MAX_TEXTIO_TEST_SIZE:
+        return
+    encoding = ENCODINGS[FuzzerInput[0] % len(ENCODINGS)]
+    errors = ERRORS[FuzzerInput[1] % len(ERRORS)]
+    newline = NEWLINES[FuzzerInput[2] % len(NEWLINES)]
+    op = FuzzerInput[3]
+    chunk = 1 + FuzzerInput[4] % 64
+    data = FuzzerInput[5:]
+
+    # Only our own constant parameters are used here; a failure would be
+    # a bug and is allowed to propagate.
+    wrapper = io.TextIOWrapper(
+        io.BytesIO(data), encoding=encoding, errors=errors, newline=newline
+    )
+    try:
+        pattern = op % 4
+        if pattern == 0:
+            wrapper.read()
+        elif pattern == 1:
+            while wrapper.readline():
+                pass
+        elif pattern == 2:
+            while wrapper.read(chunk):
+                pass
+        else:
+            for _ in wrapper:
+                pass
+        wrapper.close()
+    except UnicodeDecodeError:
+        pass