diff --git a/games-simulation/openttd/Manifest b/games-simulation/openttd/Manifest
index 88a3a4e5e5c7..b3e9ac8ea870 100644
--- a/games-simulation/openttd/Manifest
+++ b/games-simulation/openttd/Manifest
@@ -1 +1,2 @@
 DIST openttd-15.2-source.tar.xz 8514360 BLAKE2B 2d68e6ac013a0cfe4b60896017c27a2a0606a520a52bfe7e7dd1ffec16d0e658dfc7ead2216d8ffd9a0ec94e7f00c4d7d099df60d4dc50ebf32b0bcd83d2a338 SHA512 30bc2f91791a7ed7b3cb83b3677b3b66a35507524638834f33c5d46d8a2a662bdc1d498c7300ee2a72e52a3d3318965d6ec858f3c90070ee8983fac46cd2eddb
+DIST openttd-15.3-source.tar.xz 8531992 BLAKE2B c88253714a2abfa2dc36767bc3a24dcfecd68d5ec6fe06ef3fe7a7ea1747de2caca67332c20f0b4fbb5375caa8c26b45975937df6ded330aceaecf1d0497d05d SHA512 966b97450eb9509d50652596d3af92554e46e65cb36e41c7fe2c46dac84b397b2b693f1f0bf6308aabe1e8f5ff8a90ece99ccbe34cbb3bb723a389324269b771
diff --git a/games-simulation/openttd/openttd-15.3.ebuild b/games-simulation/openttd/openttd-15.3.ebuild
new file mode 100644
index 000000000000..769e22a8c263
--- /dev/null
+++ b/games-simulation/openttd/openttd-15.3.ebuild
@@ -0,0 +1,137 @@
+# Copyright 1999-2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit cmake xdg
+
+DESCRIPTION="A clone of Transport Tycoon Deluxe"
+HOMEPAGE="https://www.openttd.org/"
+
+if [[ ${PV} == 9999 ]] ; then
+	EGIT_REPO_URI="https://github.com/OpenTTD/OpenTTD"
+	inherit git-r3
+else
+	SRC_URI="https://cdn.openttd.org/openttd-releases/${PV}/${P}-source.tar.xz"
+
+	KEYWORDS="~amd64 ~arm64 ~ppc64 ~x86"
+fi
+
+LICENSE="GPL-2"
+SLOT="0"
+IUSE="allegro cpu_flags_x86_sse debug dedicated +fluidsynth icu +lzma lzo +openmedia +png +sdl timidity +truetype +zlib"
+REQUIRED_USE="!dedicated? ( || ( allegro sdl ) )"
+
+RDEPEND="
+	net-misc/curl
+	dedicated? (
+		acct-group/openttd
+		acct-user/openttd
+		app-misc/dtach
+	)
+	!dedicated? (
+		media-libs/libogg
+		media-libs/opusfile
+		allegro? ( media-libs/allegro:5 )
+		fluidsynth? ( media-sound/fluidsynth )
+		icu? (
+			>=dev-libs/icu-58.1:=
+			media-libs/harfbuzz
+		)
+		sdl? ( media-libs/libsdl2[sound,video] )
+		truetype? (
+			media-libs/fontconfig
+			media-libs/freetype:2
+			virtual/zlib:=
+		)
+	)
+	lzma? ( app-arch/xz-utils )
+	lzo? ( dev-libs/lzo:2 )
+	png? ( media-libs/libpng:= )
+	zlib? ( virtual/zlib:= )
+"
+DEPEND="${RDEPEND}"
+BDEPEND="
+	>=games-util/grfcodec-6.0.6_p20210310
+	virtual/pkgconfig
+"
+PDEPEND="
+	!dedicated? (
+		openmedia? (
+			>=games-misc/openmsx-0.4.0
+			>=games-misc/opensfx-1.0.1
+		)
+	)
+	openmedia? ( >=games-misc/opengfx-0.6.1 )
+	timidity? ( media-sound/timidity++ )
+"
+
+DOCS=( docs/directory_structure.md )
+
+PATCHES=(
+	"${FILESDIR}/${PN}-1.11.2_dont_compress_man.patch"
+)
+
+src_prepare() {
+	# Drop automagic LTO usage
+	sed -i -e '/check_ipo_supported(RESULT IPO_FOUND)/d' CMakeLists.txt || die
+
+	# Don't force _FORTIFY_SOURCE via CMake
+	# (we already set it in the toolchain by default with a minimum level
+	# of _FORTIFY_SOURCE=2)
+	sed -i -e '/-D_FORTIFY_SOURCE/d' cmake/CompileFlags.cmake || die
+
+	cmake_src_prepare
+}
+
+src_configure() {
+	local mycmakeargs=(
+		-DCMAKE_INSTALL_BINDIR=bin
+		-DCMAKE_INSTALL_DATADIR=share
+		-DOPTION_DEDICATED=$(usex dedicated)
+		-DOPTION_USE_ASSERTS=$(usex debug)
+		-DCMAKE_DISABLE_FIND_PACKAGE_Allegro=$(usex !allegro)
+		-DCMAKE_DISABLE_FIND_PACKAGE_Freetype=$(usex !truetype)
+		-DCMAKE_DISABLE_FIND_PACKAGE_Fontconfig=$(usex !truetype)
+		-DCMAKE_DISABLE_FIND_PACKAGE_Fluidsynth=$(usex !fluidsynth)
+		-DCMAKE_DISABLE_FIND_PACKAGE_ICU=$(usex !icu)
+		-DCMAKE_DISABLE_FIND_PACKAGE_Harfbuzz=$(usex !icu)
+		-DCMAKE_DISABLE_FIND_PACKAGE_LibLZMA=$(usex !lzma)
+		-DCMAKE_DISABLE_FIND_PACKAGE_LZO=$(usex !lzo)
+		-DCMAKE_DISABLE_FIND_PACKAGE_PNG=$(usex !png)
+		-DCMAKE_DISABLE_FIND_PACKAGE_SDL2=$(usex !sdl)
+		-DCMAKE_DISABLE_FIND_PACKAGE_SSE=$(usex !cpu_flags_x86_sse)
+		-DCMAKE_DISABLE_FIND_PACKAGE_ZLIB=$(usex !zlib)
+	)
+
+	cmake_src_configure
+}
+
+src_install() {
+	cmake_src_install
+
+	if use dedicated ; then
+		newconfd "${FILESDIR}"/openttd.confd-r1 openttd
+		newinitd "${FILESDIR}"/openttd.initd-r3 openttd
+	fi
+}
+
+pkg_postinst() {
+	xdg_pkg_postinst
+
+	if ! use openmedia ; then
+		elog
+		elog "OpenTTD was compiled without the 'openmedia' USE flag."
+		elog
+		elog "In order to play, you must at least install"
+		elog "games-misc/opengfx, and games-misc/opensfx, or copy the "
+		elog "following 6 files from a version of Transport Tycoon Deluxe"
+		elog "(Windows or DOS) to shared or personal location."
+		elog "See ${EROOT}/usr/share/doc/${PF}/directory_structure.md for more info."
+		elog
+		elog "From the Windows version you need: "
+		elog "sample.cat trg1r.grf trgcr.grf trghr.grf trgir.grf trgtr.grf"
+		elog "OR from the DOS version you need: "
+		elog "SAMPLE.CAT TRG1.GRF TRGC.GRF TRGH.GRF TRGI.GRF TRGT.GRF"
+	fi
+}