diff --git a/code/__HELPERS/roundend.dm b/code/__HELPERS/roundend.dm
index 259d89bef9f..89c343b2616 100644
--- a/code/__HELPERS/roundend.dm
+++ b/code/__HELPERS/roundend.dm
@@ -469,10 +469,11 @@
 	var/station_vault = 0
 	///How many players joined the round.
 	var/total_players = GLOB.joined_player_list.len
-	for(var/i in SSeconomy.bank_accounts)
-		if(istype(i, /datum/bank_account/department) || istype(i, /datum/bank_account/remote))
+	var/list/typecache_bank = typecacheof(list(/datum/bank_account/department, /datum/bank_account/remote))
+	for(var/i in SSeconomy.bank_accounts_by_id)
+		var/datum/bank_account/current_acc = SSeconomy.bank_accounts_by_id[i]
+		if(typecache_bank[current_acc.type])
 			continue
-		var/datum/bank_account/current_acc = i
 		station_vault += current_acc.account_balance
 		if(!mr_moneybags || mr_moneybags.account_balance < current_acc.account_balance)
 			mr_moneybags = current_acc
diff --git a/code/controllers/subsystem/economy.dm b/code/controllers/subsystem/economy.dm
index 16f242d2a83..1f23fde6547 100644
--- a/code/controllers/subsystem/economy.dm
+++ b/code/controllers/subsystem/economy.dm
@@ -45,7 +45,11 @@ SUBSYSTEM_DEF(economy)
 							"adamantine" = 750,
 							// tier 4
 							"rainbow" = 1000)
-	var/list/bank_accounts = list() //List of normal accounts (not department accounts)
+	/**
+	  * List of normal (no department ones) accounts' identifiers with associated datum accounts, for big O performance.
+	  * A list of sole account datums can be obtained with flatten_list(), another variable would be redundant rn.
+	  */
+	var/list/bank_accounts_by_id = list()
 	var/list/dep_cards = list()
 	/// A var that collects the total amount of credits owned in player accounts on station, reset and recounted on fire()
 	var/station_total = 0
@@ -76,14 +80,14 @@ SUBSYSTEM_DEF(economy)
 	car_payout() // Cargo's natural gain in the cash moneys.
 	station_total = 0
 	station_target_buffer += STATION_TARGET_BUFFER
-	for(var/account in bank_accounts)
-		var/datum/bank_account/bank_account = account
+	for(var/account in bank_accounts_by_id)
+		var/datum/bank_account/bank_account = bank_accounts_by_id[account]
 		bank_account.payday(1)
 		if(bank_account?.account_job)
 			temporary_total += (bank_account.account_job.paycheck * STARTING_PAYCHECKS)
 		if(!istype(bank_account, /datum/bank_account/department))
 			station_total += bank_account.account_balance
-	station_target = max(round(temporary_total / max(bank_accounts.len * 2, 1)) + station_target_buffer, 1)
+	station_target = max(round(temporary_total / max(bank_accounts_by_id.len * 2, 1)) + station_target_buffer, 1)
 	if(!market_crashing)
 		price_update()
 
@@ -184,7 +188,7 @@ SUBSYSTEM_DEF(economy)
   * The goal here is that if you want to spend money, you'll have to get it, and the most efficient method is typically from other players.
   **/
 /datum/controller/subsystem/economy/proc/inflation_value()
-	if(!bank_accounts.len)
+	if(!bank_accounts_by_id.len)
 		return 1
-	inflation_value = max(round(((station_total / bank_accounts.len) / station_target), 0.1), 1.0)
+	inflation_value = max(round(((station_total / bank_accounts_by_id.len) / station_target), 0.1), 1.0)
 	return inflation_value
diff --git a/code/game/objects/items/cards_ids.dm b/code/game/objects/items/cards_ids.dm
index 0014d9768a0..482991c317c 100644
--- a/code/game/objects/items/cards_ids.dm
+++ b/code/game/objects/items/cards_ids.dm
@@ -200,17 +200,16 @@
 		to_chat(user, "<span class='warning'>The account ID was already assigned to this card.</span>")
 		return
 
-	for(var/A in SSeconomy.bank_accounts)
-		var/datum/bank_account/B = A
-		if(B.account_id == new_bank_id)
-			if (old_account)
-				old_account.bank_cards -= src
+	var/datum/bank_account/B = SSeconomy.bank_accounts_by_id["[new_bank_id]"]
+	if(B)
+		if (old_account)
+			old_account.bank_cards -= src
 
-			B.bank_cards += src
-			registered_account = B
-			to_chat(user, "<span class='notice'>The provided account has been linked to this ID card.</span>")
+		B.bank_cards += src
+		registered_account = B
+		to_chat(user, "<span class='notice'>The provided account has been linked to this ID card.</span>")
 
-			return TRUE
+		return TRUE
 
 	to_chat(user, "<span class='warning'>The account ID number provided is invalid.</span>")
 	return
@@ -419,12 +418,11 @@ update_label()
 				if(ishuman(user))
 					var/mob/living/carbon/human/accountowner = user
 
-					for(var/bank_account in SSeconomy.bank_accounts)
-						var/datum/bank_account/account = bank_account
-						if(account.account_id == accountowner.account_id)
-							account.bank_cards += src
-							registered_account = account
-							to_chat(user, "<span class='notice'>Your account number has been automatically assigned.</span>")
+					var/datum/bank_account/account = SSeconomy.bank_accounts_by_id["[accountowner.account_id]"]
+					if(account)
+						account.bank_cards += src
+						registered_account = account
+						to_chat(user, "<span class='notice'>Your account number has been automatically assigned.</span>")
 			return
 		else if (popup_input == "Forge/Reset" && forged)
 			registered_name = initial(registered_name)
diff --git a/code/game/objects/items/crab17.dm b/code/game/objects/items/crab17.dm
index 94a199ec2d7..5ccfe8ee854 100644
--- a/code/game/objects/items/crab17.dm
+++ b/code/game/objects/items/crab17.dm
@@ -21,7 +21,7 @@
 		var/turf/targetturf = get_safe_random_station_turf()
 		if (!targetturf)
 			return FALSE
-		var/list/accounts_to_rob = SSeconomy.bank_accounts.Copy()
+		var/list/accounts_to_rob = flatten_list(SSeconomy.bank_accounts_by_id)
 		var/mob/living/carbon/human/H = user
 		accounts_to_rob -= H.get_bank_account()
 		for(var/i in accounts_to_rob)
@@ -161,7 +161,7 @@
 	return ..()
 
 /obj/structure/checkoutmachine/proc/start_dumping()
-	accounts_to_rob = SSeconomy.bank_accounts.Copy()
+	accounts_to_rob = flatten_list(SSeconomy.bank_accounts_by_id)
 	accounts_to_rob -= bogdanoff.get_bank_account()
 	for(var/i in accounts_to_rob)
 		var/datum/bank_account/B = i
@@ -172,7 +172,8 @@
 	var/percentage_lost = (rand(5, 15) / 100)
 	for(var/i in accounts_to_rob)
 		var/datum/bank_account/B = i
-		if(!B.being_dumped)
+		if(!(B?.being_dumped))
+			accounts_to_rob -= B
 			continue
 		var/amount = B.account_balance * percentage_lost
 		var/datum/bank_account/account = bogdanoff.get_bank_account()
@@ -189,7 +190,8 @@
 /obj/structure/checkoutmachine/proc/stop_dumping()
 	for(var/i in accounts_to_rob)
 		var/datum/bank_account/B = i
-		B.being_dumped = FALSE
+		if(B)
+			B.being_dumped = FALSE
 
 /obj/effect/dumpeet_fall //Falling pod
 	name = ""
diff --git a/code/modules/economy/account.dm b/code/modules/economy/account.dm
index 8bb1cb56539..19f4f11aaee 100644
--- a/code/modules/economy/account.dm
+++ b/code/modules/economy/account.dm
@@ -13,18 +13,43 @@
 	var/bounty_timer = 0
 
 /datum/bank_account/New(newname, job, modifier = 1)
-	if(add_to_accounts)
-		SSeconomy.bank_accounts += src
 	account_holder = newname
 	account_job = job
-	account_id = rand(111111,999999)
 	payday_modifier = modifier
+	setup_unique_account_id()
 
 /datum/bank_account/Destroy()
 	if(add_to_accounts)
-		SSeconomy.bank_accounts -= src
+		SSeconomy.bank_accounts_by_id -= "[account_id]"
 	return ..()
 
+/// Proc guarantees the account_id possesses a unique number. If it doesn't, it tries to find a unique alternative. It then adds it to the `SSeconomy.bank_accounts_by_id` global list.
+/datum/bank_account/proc/setup_unique_account_id()
+	if(account_id && !SSeconomy.bank_accounts_by_id["[account_id]"])
+		SSeconomy.bank_accounts_by_id["[account_id]"] = src
+		return //Already unique
+	for(var/i in 1 to 1000)
+		account_id = rand(111111, 999999)
+		if(!SSeconomy.bank_accounts_by_id["[account_id]"])
+			break
+	if(SSeconomy.bank_accounts_by_id["[account_id]"])
+		stack_trace("Unable to find a unique account ID, substituting currently existing account of id [account_id].")
+	SSeconomy.bank_accounts_by_id["[account_id]"] = src
+
+/datum/bank_account/vv_edit_var(var_name, var_value) // just so you don't have to do it manually
+	var/old_id = account_id
+	. = ..()
+	switch(var_name)
+		if(NAMEOF(src, account_id))
+			if(add_to_accounts)
+				SSeconomy.bank_accounts_by_id -= "[old_id]"
+				setup_unique_account_id()
+		if(NAMEOF(src, add_to_accounts))
+			if(add_to_accounts)
+				setup_unique_account_id()
+			else
+				SSeconomy.bank_accounts_by_id -= "[account_id]"
+
 /datum/bank_account/proc/dumpeet()
 	being_dumped = TRUE
 
diff --git a/code/modules/events/market_crash.dm b/code/modules/events/market_crash.dm
index a2e763ea8b2..8fcf5d44fe4 100644
--- a/code/modules/events/market_crash.dm
+++ b/code/modules/events/market_crash.dm
@@ -27,10 +27,7 @@
 
 /datum/round_event/market_crash/start()
 	. = ..()
-	var/num_accounts = 0
-	for(var/A in SSeconomy.bank_accounts)
-		num_accounts += 1
-	market_dip = rand(1000,10000) * num_accounts
+	market_dip = rand(1000,10000) * length(SSeconomy.bank_accounts_by_id)
 	SSeconomy.station_target = max(SSeconomy.station_target - market_dip, 1)
 	SSeconomy.price_update()
 	SSeconomy.market_crashing = TRUE
diff --git a/code/modules/jobs/job_types/_job.dm b/code/modules/jobs/job_types/_job.dm
index 200c47eca93..9f40deadc64 100644
--- a/code/modules/jobs/job_types/_job.dm
+++ b/code/modules/jobs/job_types/_job.dm
@@ -243,12 +243,10 @@
 		if(H.age)
 			C.registered_age = H.age
 		C.update_label()
-		for(var/A in SSeconomy.bank_accounts)
-			var/datum/bank_account/B = A
-			if(B.account_id == H.account_id)
-				C.registered_account = B
-				B.bank_cards += C
-				break
+		var/datum/bank_account/B = SSeconomy.bank_accounts_by_id["[H.account_id]"]
+		if(B && B.account_id == H.account_id)
+			C.registered_account = B
+			B.bank_cards += C
 		H.sec_hud_set_ID()
 
 	var/obj/item/pda/PDA = H.get_item_by_slot(pda_slot)