diff --git a/eth/backend.go b/eth/backend.go
index 064f58c24a..b9185f3348 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -406,7 +406,7 @@ func New(stack *node.Node, config *ethconfig.Config) (*Ethereum, error) {
 	if eth.APIBackend.allowUnprotectedTxs {
 		log.Info("Unprotected transactions allowed")
 	}
-	eth.APIBackend.gpo = gasprice.NewOracle(eth.APIBackend, config.GPO, config.Miner.GasPrice)
+	eth.APIBackend.gpo = gasprice.NewOracle(eth.APIBackend, config.GPO, config.Miner.GasPrice, config.Miner.MaxDABlockSize)
 
 	if config.RollupSequencerHTTP != "" {
 		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
diff --git a/eth/gasprice/feehistory_test.go b/eth/gasprice/feehistory_test.go
index 3fc942953e..f8ce7614da 100644
--- a/eth/gasprice/feehistory_test.go
+++ b/eth/gasprice/feehistory_test.go
@@ -68,7 +68,7 @@ func testFeeHistory(t *testing.T, opStack bool) {
 			MaxBlockHistory:  c.maxBlock,
 		}
 		backend := newTestBackend(t, big.NewInt(16), big.NewInt(28), c.pending, opStack)
-		oracle := NewOracle(backend, config, nil)
+		oracle := NewOracle(backend, config, nil, big.NewInt(1000000))
 
 		first, reward, baseFee, ratio, blobBaseFee, blobRatio, err := oracle.FeeHistory(context.Background(), c.count, c.last, c.percent)
 		backend.teardown()
diff --git a/eth/gasprice/gasprice.go b/eth/gasprice/gasprice.go
index 58a59cbdb9..e9e64bbf38 100644
--- a/eth/gasprice/gasprice.go
+++ b/eth/gasprice/gasprice.go
@@ -76,6 +76,7 @@ type Oracle struct {
 
 	checkBlocks, percentile           int
 	maxHeaderHistory, maxBlockHistory uint64
+	maxDABlockSize                    *big.Int
 
 	historyCache *lru.Cache[cacheKey, processedFees]
 
@@ -84,7 +85,7 @@ type Oracle struct {
 
 // NewOracle returns a new gasprice oracle which can recommend suitable
 // gasprice for newly created transaction.
-func NewOracle(backend OracleBackend, params Config, startPrice *big.Int) *Oracle {
+func NewOracle(backend OracleBackend, params Config, startPrice *big.Int, maxDABlockSize *big.Int) *Oracle {
 	blocks := params.Blocks
 	if blocks < 1 {
 		blocks = 1
@@ -123,6 +124,9 @@ func NewOracle(backend OracleBackend, params Config, startPrice *big.Int) *Oracl
 	if startPrice == nil {
 		startPrice = new(big.Int)
 	}
+	if maxDABlockSize == nil {
+		maxDABlockSize = new(big.Int)
+	}
 
 	cache := lru.NewCache[cacheKey, processedFees](2048)
 	headEvent := make(chan core.ChainHeadEvent, 1)
@@ -153,6 +157,7 @@ func NewOracle(backend OracleBackend, params Config, startPrice *big.Int) *Oracl
 		percentile:       percent,
 		maxHeaderHistory: maxHeaderHistory,
 		maxBlockHistory:  maxBlockHistory,
+		maxDABlockSize:   maxDABlockSize,
 		historyCache:     cache,
 	}
 
diff --git a/eth/gasprice/gasprice_test.go b/eth/gasprice/gasprice_test.go
index 1d130c311d..a6aec8f3cc 100644
--- a/eth/gasprice/gasprice_test.go
+++ b/eth/gasprice/gasprice_test.go
@@ -278,7 +278,7 @@ func TestSuggestTipCap(t *testing.T) {
 	}
 	for _, c := range cases {
 		backend := newTestBackend(t, c.fork, nil, false, false)
-		oracle := NewOracle(backend, config, big.NewInt(params.GWei))
+		oracle := NewOracle(backend, config, big.NewInt(params.GWei), big.NewInt(1000000))
 
 		// The gas price sampled is: 32G, 31G, 30G, 29G, 28G, 27G
 		got, err := oracle.SuggestTipCap(context.Background())
diff --git a/eth/gasprice/optimism-gasprice.go b/eth/gasprice/optimism-gasprice.go
index 94686f2644..76d627a106 100644
--- a/eth/gasprice/optimism-gasprice.go
+++ b/eth/gasprice/optimism-gasprice.go
@@ -38,8 +38,8 @@ import (
 func (oracle *Oracle) SuggestOptimismPriorityFee(ctx context.Context, h *types.Header, headHash common.Hash) *big.Int {
 	suggestion := new(big.Int).Set(oracle.minSuggestedPriorityFee)
 
-	// find the maximum gas used by any of the transactions in the block to use as the capacity
-	// margin
+	// find the maximum gas used by any of the transactions in the block to use as the gas limit
+	// capacity margin
 	receipts, err := oracle.backend.GetReceipts(ctx, headHash)
 	if receipts == nil || err != nil {
 		log.Error("failed to get block receipts", "err", err)
@@ -59,19 +59,54 @@ func (oracle *Oracle) SuggestOptimismPriorityFee(ctx context.Context, h *types.H
 		return suggestion
 	}
 
-	if h.GasUsed+maxTxGasUsed > h.GasLimit {
-		// A block is "at capacity" if, when it is built, there is a pending tx in the txpool that
-		// could not be included because the block's gas limit would be exceeded. Since we don't
-		// have access to the txpool, we instead adopt the following heuristic: consider a block as
-		// at capacity if the total gas consumed by its transactions is within max-tx-gas-used of
-		// the block limit, where max-tx-gas-used is the most gas used by any one transaction
-		// within the block. This heuristic is almost perfectly accurate when transactions always
-		// consume the same amount of gas, but becomes less accurate as tx gas consumption begins
-		// to vary. The typical error is we assume a block is at capacity when it was not because
-		// max-tx-gas-used will in most cases over-estimate the "capacity margin". But it's better
-		// to err on the side of returning a higher-than-needed suggestion than a lower-than-needed
-		// one in order to satisfy our desire for high chance of inclusion and rising fees under
-		// high demand.
+	// find the maximum transaction size by any of the transactions in the block to use as the block
+	// size limit capacity margin
+	var (
+		maxTxSizeUsed   uint64
+		totalTxSizeUsed uint64
+	)
+	block, err := oracle.backend.BlockByNumber(ctx, rpc.BlockNumber(h.Number.Int64()))
+	if block == nil || err != nil {
+		log.Error("failed to get last block", "err", err)
+		return suggestion
+	}
+	txs := block.Transactions()
+
+	for i := range txs {
+		su := txs[i].Size()
+		if su > maxTxSizeUsed {
+			maxTxSizeUsed = su
+		}
+		totalTxSizeUsed = totalTxSizeUsed + su
+	}
+
+	if maxTxSizeUsed > oracle.maxDABlockSize.Uint64() {
+		log.Error("found tx consuming more size than the block size limit", "size", maxTxSizeUsed)
+		return suggestion
+	}
+
+	if h.GasUsed+maxTxGasUsed > h.GasLimit ||
+		totalTxSizeUsed+maxTxSizeUsed > oracle.maxDABlockSize.Uint64() {
+		// There are two cases that represent a block is "at capacity":
+		//   1. When building the block, there is a pending transaction in the txpool that could not be
+		//      included because adding it would exceed the block's gas limit.
+		//   2. Or, there is a pending transaction that could not be included because adding it would
+		//      exceed the block's transaction payload size (block size limit).
+		//
+		// Since we don't have access to the txpool, we instead adopt the following heuristic:
+		// consider a block as at capacity if either:
+		//   - the total gas consumed by its transactions is within max-tx-gas-used of the block gas
+		//     limit, where max-tx-gas-used is the most gas used by any one transaction within the block, or
+		//   - the total transaction payload size is within max-tx-size-used of the block size limit,
+		//     where max-tx-size-used is the largest transaction size in the block.
+		//
+		// This heuristic is almost perfectly accurate when transactions always consume the same amount
+		// of gas and have similar sizes, but becomes less accurate as gas usage or payload size varies
+		// between transactions. The typical error is that we assume a block is at capacity when it was
+		// not, because max-tx-gas-used or max-tx-size-used will in most cases over-estimate the
+		// "capacity margin". But it's better to err on the side of returning a higher-than-needed
+		// suggestion than a lower-than-needed one, in order to satisfy our desire for high chance of
+		// inclusion and rising fees under high demand.
 		block, err := oracle.backend.BlockByNumber(ctx, rpc.BlockNumber(h.Number.Int64()))
 		if block == nil || err != nil {
 			log.Error("failed to get last block", "err", err)
diff --git a/eth/gasprice/optimism-gasprice_test.go b/eth/gasprice/optimism-gasprice_test.go
index 94599cdd78..024e8362ea 100644
--- a/eth/gasprice/optimism-gasprice_test.go
+++ b/eth/gasprice/optimism-gasprice_test.go
@@ -136,7 +136,7 @@ func TestSuggestOptimismPriorityFee(t *testing.T) {
 	}
 	for i, c := range cases {
 		backend := newOpTestBackend(t, c.txdata)
-		oracle := NewOracle(backend, Config{MinSuggestedPriorityFee: minSuggestion}, big.NewInt(params.GWei))
+		oracle := NewOracle(backend, Config{MinSuggestedPriorityFee: minSuggestion}, big.NewInt(params.GWei), big.NewInt(1000000))
 		got := oracle.SuggestOptimismPriorityFee(context.Background(), backend.block.Header(), backend.block.Hash())
 		if got.Cmp(c.want) != 0 {
 			t.Errorf("Gas price mismatch for test case %d: want %d, got %d", i, c.want, got)