diff --git a/src/proto_alpha/lib_parameters/default_parameters.ml b/src/proto_alpha/lib_parameters/default_parameters.ml
index fe7b8fdcd43d612df8f967e15706e5abc115a7d0..6a3d8ff6a500104da29f4bc2c508ed71e3051bfa 100644
--- a/src/proto_alpha/lib_parameters/default_parameters.ml
+++ b/src/proto_alpha/lib_parameters/default_parameters.ml
@@ -111,7 +111,7 @@ let constants_mainnet =
        the capability to have two rollups at full speed on
        mainnet (as long as they do not reach scalability
        issues related to proof size). *)
-    tx_rollup_hard_size_limit_per_inbox = 250_000;
+    tx_rollup_hard_size_limit_per_inbox = 500_000;
     tx_rollup_hard_size_limit_per_message = 5_000;
     tx_rollup_commitment_bond = Tez.of_mutez_exn 10_000_000_000L;
     tx_rollup_finality_period;
diff --git a/src/proto_alpha/lib_protocol/raw_context.ml b/src/proto_alpha/lib_protocol/raw_context.ml
index 27b815b0b9a79ec46772a00ff497815b3d30aa5d..8aca02e969812b5e236564fabe1651b8c753aefd 100644
--- a/src/proto_alpha/lib_protocol/raw_context.ml
+++ b/src/proto_alpha/lib_protocol/raw_context.ml
@@ -912,7 +912,7 @@ let prepare_first_block ~level ~timestamp ctxt =
                the capability to have two rollups at full speed on
                mainnet (as long as they do not reach scalability
                issues related to proof size). *)
-            tx_rollup_hard_size_limit_per_inbox = 250_000;
+            tx_rollup_hard_size_limit_per_inbox = 500_000;
             tx_rollup_hard_size_limit_per_message = 5_000;
             (* Tickets are transmitted in batches in the
                [Tx_rollup_dispatch_tickets] operation.
diff --git a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
index 7051e707d89730b3b2bdf86abbcd5464471768be..045830ba5b04479e9906d13661164429d6bfc4a0 100644
--- a/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/operations/test_tx_rollup.ml
@@ -926,7 +926,7 @@ let fill_inbox b tx_rollup contract contents k =
        consumed by an operation. We set a lower (arbitrary) limit to
        be able to reach the size limit of an operation. *)
     Op.tx_rollup_submit_batch
-      ~gas_limit:(Gas.Arith.integral_of_int_exn 100_000)
+      ~gas_limit:(Gas.Arith.integral_of_int_exn 20_000)
       ~counter
       (I i)
       contract
diff --git a/tezt/_regressions/rpc/alpha.client.others.out b/tezt/_regressions/rpc/alpha.client.others.out
index 95d0206d0a8064b2cb3ebd5ea371af78853b2e86..d0754e8ebb5fc2c447eaadb9ee9e76fbc62bca5c 100644
--- a/tezt/_regressions/rpc/alpha.client.others.out
+++ b/tezt/_regressions/rpc/alpha.client.others.out
@@ -30,7 +30,7 @@ rpc/alpha.client.others.out
     { "numerator": 1, "denominator": 2 }, "cache_script_size": 100000000,
   "cache_stake_distribution_cycles": 8, "cache_sampler_state_cycles": 8,
   "tx_rollup_enable": true, "tx_rollup_origination_size": 4000,
-  "tx_rollup_hard_size_limit_per_inbox": 250000,
+  "tx_rollup_hard_size_limit_per_inbox": 500000,
   "tx_rollup_hard_size_limit_per_message": 5000,
   "tx_rollup_max_withdrawals_per_batch": 15,
   "tx_rollup_commitment_bond": "10000000000",
diff --git a/tezt/_regressions/rpc/alpha.light.others.out b/tezt/_regressions/rpc/alpha.light.others.out
index 0c0afde88522b49b41ea818ec344885abdc337e4..4a2f7a1f90b2baf96e76a07eaacd6850620a7684 100644
--- a/tezt/_regressions/rpc/alpha.light.others.out
+++ b/tezt/_regressions/rpc/alpha.light.others.out
@@ -30,7 +30,7 @@ rpc/alpha.light.others.out
     { "numerator": 1, "denominator": 2 }, "cache_script_size": 100000000,
   "cache_stake_distribution_cycles": 8, "cache_sampler_state_cycles": 8,
   "tx_rollup_enable": true, "tx_rollup_origination_size": 4000,
-  "tx_rollup_hard_size_limit_per_inbox": 250000,
+  "tx_rollup_hard_size_limit_per_inbox": 500000,
   "tx_rollup_hard_size_limit_per_message": 5000,
   "tx_rollup_max_withdrawals_per_batch": 15,
   "tx_rollup_commitment_bond": "10000000000",
diff --git a/tezt/_regressions/rpc/alpha.proxy.others.out b/tezt/_regressions/rpc/alpha.proxy.others.out
index 1da4080a61e2c112011fec555397049345968010..c48ac5b3ccc23cf6574f44b5270ef8d8cc139b2c 100644
--- a/tezt/_regressions/rpc/alpha.proxy.others.out
+++ b/tezt/_regressions/rpc/alpha.proxy.others.out
@@ -30,7 +30,7 @@ rpc/alpha.proxy.others.out
     { "numerator": 1, "denominator": 2 }, "cache_script_size": 100000000,
   "cache_stake_distribution_cycles": 8, "cache_sampler_state_cycles": 8,
   "tx_rollup_enable": true, "tx_rollup_origination_size": 4000,
-  "tx_rollup_hard_size_limit_per_inbox": 250000,
+  "tx_rollup_hard_size_limit_per_inbox": 500000,
   "tx_rollup_hard_size_limit_per_message": 5000,
   "tx_rollup_max_withdrawals_per_batch": 15,
   "tx_rollup_commitment_bond": "10000000000",
diff --git a/tezt/_regressions/rpc/alpha.proxy_server_data_dir.others.out b/tezt/_regressions/rpc/alpha.proxy_server_data_dir.others.out
index fa38011cff5ce258cda99da9cd0abfa11b3f455c..83c1d15fd3eadde81ff79257e26cea0e58291770 100644
--- a/tezt/_regressions/rpc/alpha.proxy_server_data_dir.others.out
+++ b/tezt/_regressions/rpc/alpha.proxy_server_data_dir.others.out
@@ -30,7 +30,7 @@ rpc/alpha.proxy_server_data_dir.others.out
     { "numerator": 1, "denominator": 2 }, "cache_script_size": 100000000,
   "cache_stake_distribution_cycles": 8, "cache_sampler_state_cycles": 8,
   "tx_rollup_enable": true, "tx_rollup_origination_size": 4000,
-  "tx_rollup_hard_size_limit_per_inbox": 250000,
+  "tx_rollup_hard_size_limit_per_inbox": 500000,
   "tx_rollup_hard_size_limit_per_message": 5000,
   "tx_rollup_max_withdrawals_per_batch": 15,
   "tx_rollup_commitment_bond": "10000000000",
diff --git a/tezt/_regressions/rpc/alpha.proxy_server_rpc.others.out b/tezt/_regressions/rpc/alpha.proxy_server_rpc.others.out
index a0cf069c33dedf954b9e8a585dc52a0d7038fbf4..187faa67947552afd282d591bea2aa2ac5a118c9 100644
--- a/tezt/_regressions/rpc/alpha.proxy_server_rpc.others.out
+++ b/tezt/_regressions/rpc/alpha.proxy_server_rpc.others.out
@@ -30,7 +30,7 @@ rpc/alpha.proxy_server_rpc.others.out
     { "numerator": 1, "denominator": 2 }, "cache_script_size": 100000000,
   "cache_stake_distribution_cycles": 8, "cache_sampler_state_cycles": 8,
   "tx_rollup_enable": true, "tx_rollup_origination_size": 4000,
-  "tx_rollup_hard_size_limit_per_inbox": 250000,
+  "tx_rollup_hard_size_limit_per_inbox": 500000,
   "tx_rollup_hard_size_limit_per_message": 5000,
   "tx_rollup_max_withdrawals_per_batch": 15,
   "tx_rollup_commitment_bond": "10000000000",