EXHIBIT 99.1

Santander Drive Auto Receivables Trust 2015-4

Class A-1 0.50000% Asset Backed Notes

Class A-2-A 1.20% Asset Backed Notes

Class A-2-B LIBOR + 0.70% Asset Backed Notes

Class A-3 1.58% Asset Backed Notes

Class B 2.26% Asset Backed Notes

Class C 2.97% Asset Backed Notes

Class D 3.53% Asset Backed Notes

Class E 4.54% Asset Backed Notes

Servicer’s Certificate

This Servicer’s Certificate has been prepared pursuant to Section 4.6 of the Sale and Servicing Agreement among Santander Drive Auto Receivables Trust 2015-4, as Issuer, Santander Consumer USA Inc. as Servicer, Santander Drive Auto Receivables LLC, as Seller, and Wells Fargo Bank, National Association, as Indenture Trustee, dated as of August 26, 2015. Defined terms have the meanings assigned to them in the Sale and Servicing Agreement or in other Transaction Documents.

Collection Period Beginning:	03/01/2019
Collection Period Ending:	03/31/2019
Previous Payment Date/Close Date:	03/15/2019
Payment Date	04/15/2019
Days of Interest for Period:	31
Days in Collection Period:	31
Months Seasoned:	44

							Original
Purchases	Units		Cut-off Date		Closing Date		Pool Balance
Initial Purchase		71,234		07/31/2015		08/26/2015		1,408,760,769.79
Total		71,234						1,408,760,769.79

I. PRINCIPAL BALANCE CALCULATION
{1} Beginning of period aggregate Principal Balance																						{1}			267,737,630.24
Monthly principal amounts
{2} Payments Received																				{2}		10,596,570.70
{3} Repurchased Receivables																				{3}		278,703.25
{4} Defaulted Receivables																				{4}		3,646,565.22
{5} Cram Down Losses and Other Principal Adjustments																				{5}		(67.12	)
{6} Other Receivables adjustments																				{6}		—
{7} Total Principal distributable amount																						{7}			14,521,772.05
{8} End of period aggregate Principal Balance																						{8}			253,215,858.19
{9} Pool Factor																						{9}			0.179744
II. NOTE BALANCE CALCULATION
							Class A-1		Class A-2-A		Class A-2-B		Class A-3		Class B		Class C		Class D		Class E			Total
{10} Original Note Balance					{10}			203,400,000.00		188,760,000.00		188,760,000.00		153,700,000.00		170,500,000.00		183,100,000.00		109,200,000.00		70,460,000.00			1,267,880,000.00
{11} Beginning of period Note Balance					{11}			—		—		—		—		—		45,239,609.40		109,200,000.00		70,460,000.00			224,899,609.40
{12} First Allocation of Principal					{12}			—		—		—		—		—		—		—		—			—
{13} Second Allocation of Principal					{13}			—		—		—		—		—		—		—		—			—
{14} Third Allocation of Principal					{14}			—		—		—		—		—		—		—		—			—
{15} Fourth Allocation of Principal					{15}			—		—		—		—		—		—		—		—			—
{16} Fifth Allocation of Principal					{16}			—		—		—		—		—		—		—		—			—
{17} Regular Allocation of Principal					{17}			—		—		—		—		—		12,198,288.52		—		—			12,198,288.52
{18} Optional Purchase payment					{18}			—		—		—		—		—		—		—		—			—
{19} End of period Note Balance					{19}			—		—		—		—		—		33,041,320.88		109,200,000.00		70,460,000.00			212,701,320.88
{20} Note Pool Factors					{20}			—		—		—		—		—		0.180455		1.000000		1.000000			0.167761
{21} Principal payment per $1,000					{21}			—		—		—		—		—		66.62		—		—			9.62
III. RECONCILIATION OF COLLECTION ACCOUNT
Available Funds
{22} Principal Payments Received																				{22}		10,596,570.70
{23} Liquidation Proceeds																				{23}		2,014,178.31
{24} Principal on Repurchased Receivables																				{24}		468,507.22
{25} Interest on Repurchased Receivables																				{25}		24,002.19
{26} Interest collected on Receivables																				{26}		3,469,887.70
{27} Other amounts received																				{27}		28,097.31
{28} Optional Purchase Price																				{28}		—
{29} Reserve Account Excess Amount																				{29}		—
{30} Reserve Account Draw Amount																				{30}		—
{31} Total Available Funds																						{31}			16,601,243.43
Distributions
{32} Indenture Trustee Fee																				{32}		—
{33} Owner Trustee Fee																				{33}		—
Servicing Fee
	Calculated Fee	Carryover Shortfall		Change from prior period			Total
{34}	669,344.08		—		—			669,344.08												{34}		669,344.08
Class A Accrued Note Interest
	Class	Beginning Note Balance		Interest Rate			Days		Days Basis				Calculated Interest
{35}	Class A-1		—		0.50000	%		31		Actual				—						{35}		—
{36}	Class A-2-A		—		1.20	%		30		30 / 360				—						{36}		—
{37}	Class A-2-B		—		3.18	%		31		Actual				—						{37}		—
{38}	Class A-3		—		1.58	%		30		30 / 360				—						{38}		—
Class A Accrued Note Interest
	Class	Carryover Shortfall		Change from prior period			Carryover Shortfall per $1,000
{39}	Class A-1		—		—			—												{39}		—
{40}	Class A-2-A		—		—			—												{40}		—
{41}	Class A-2-B		—		—			—												{41}		—
{42}	Class A-3		—		—			—												{42}		—
{43} First Allocation of Principal																				{43}		—
Class B Accrued Note Interest
	Class	Beginning Note Balance		Interest Rate			Days		Days Basis				Calculated Interest
{44}	Class B		—		2.26	%		30		30 / 360				—						{44}		—
Class B Accrued Note Interest
	Class	Carryover Shortfall		Change from prior period			Carryover Shortfall per $1,000
{45}	Class B		—		—			—												{45}		—
{46} Second Allocation of Principal																				{46}		—
Class C Accrued Note Interest
	Class	Beginning Note Balance		Interest Rate			Days		Days Basis				Calculated Interest
{47}	Class C		45,239,609.40		2.97	%		30		30 / 360				111,968.03						{47}		111,968.03
Class C Accrued Note Interest
	Class	Carryover Shortfall		Change from prior period			Carryover Shortfall per $1,000
{48}	Class C		—		—			—												{48}		—
{49} Third Allocation of Principal																				{49}		—
Class D Accrued Note Interest
	Class	Beginning Note Balance		Interest Rate			Days		Days Basis				Calculated Interest
{50}	Class D		109,200,000.00		3.53	%		30		30 / 360				321,230.00						{50}		321,230.00
Class D Accrued Note Interest
	Class	Carryover Shortfall		Change from prior period			Carryover Shortfall per $1,000
{51}	Class D		—		—			—												{51}		—

{52} Fourth Allocation of Principal																{52}			—
Class E Accrued Note Interest
	Class	Beginning Note Balance		Interest Rate			Days		Days Basis		Calculated Interest
{53}	Class E		70,460,000.00		4.54	%		30		30 / 360		266,573.67				{53}			266,573.67
Class E Accrued Note Interest
	Class	Carryover Shortfall		Change from prior period			Carryover Shortfall per $1,000
{54}	Class E		—		—			—								{54}			—
{55} Fifth Allocation of Principal																{55}			—
{56} Reserve Account deposit																{56}			—
{57} Regular Allocation of Principal																{57}			12,198,288.52
{58} Optional Purchase Amount																{58}			—
{59} Distribution to Residual Interestholder																{59}			3,033,839.13
{60} Total Distribution Amount																			{60}			16,601,243.43
IV. RECONCILIATION OF RESERVE ACCOUNT
{61} Beginning of period Reserve Account balance													{61}	28,175,215.40
{62} Deposit to Reserve Account													{62}	—
{63} Release from Reserve Account													{63}	—
{64} End of period Reserve Account balance																			{64}			28,175,215.40
{65} Specified Reserve Account Balance (2.00% of the Pool Balance as of the Cut-Off Date)																			{65}			28,175,215.40
{66} Change in Reserve Account balance from prior period																			{66}			—
V. OVERCOLLATERALIZATION
Targeted Overcollateralization (greater of)
{67} (i) 17.00% of the Principal Balance of the Receivables at the end of the Collection Period Prior to the Class A-2 Notes being paid in full or																			{67}			43,046,695.89
{68} (ii) 16.00% of the Principal Balance of the Receivables at the end of the Collection Period After the Class A-2 Notes have been paid in full and																			{68}			40,514,537.31
{69} (iii) 1.50% of the Principal Balance of the Receivables as of the Cut-off Date																			{69}			21,131,411.55
{70} Cumulative Net Loss Trigger																			{70}			No
{71} Targeted Overcollateralization Amount in the event of a Level I Net Loss Trigger - Greater of:																			{71}			63,303,964.55
(25.00% of Receivable Principal Balance at end of Collection Period or 1.50% of Receivable Principal Balance at Cut-off)
{72} End of period Principal Balance of the Receivables																{72}			253,215,858.19
{73} End of period Note Balance																{73}			212,701,320.88
{74} Overcollateralization amount at the end of the Collection Period																			{74}			40,514,537.31
{75} Overcollateralization % at the end of the Collection Period																			{75}			16.00	%
VI. STATISTICAL DATA
															Original			Previous			Current
{76} Principal Balance of the Receivables														{76}		1,408,760,769.79			267,737,630.24			253,215,858.19
{77} Weighted average coupon of the Receivables														{77}		16.30	%		15.95	%		15.95	%
{78} Weighted average original term of the Receivables														{78}		71.11			71.79			71.82
{79} Weighted average remaining term of the Receivables														{79}		69.65			31.78			30.80
{80} Number of Receivables														{80}		71,234			22,794			22,082
VII. DELINQUENCY
															Units			Dollars			Percentage
Receivables with Scheduled Payment Delinquent
{81} 31-60 days														{81}		1,662			24,402,060.30			9.64	%
{82} 61-90 days														{82}		722			11,583,893.95			4.57	%
{83} 91-120 days														{83}		263			3,944,524.96			1.56	%
{84} 121 + days delinquent														{84}		—			—			0.00	%
{85} Total														{85}		2,647			39,930,479.21			15.77	%
VIII. REPOSSESSION INVENTORY
																		Units			Dollars
{86} Beginning of period Repossessed Inventory																{86}			277			4,412,582.05
{87} Vehicles Repossessed in current period																{87}			285			4,375,336.70
{88} Repossessed vehicles sold in current period																{88}			232			3,670,671.62
{89} Repossessed vehicles reinstated in current period																{89}			63			831,320.11
{90} Repossessed vehicle adjustment in current period																{90}			(3	)		(32,284.16	)
{91} End of period Repossessed Inventory																{91}			264			4,253,642.86
IX. CUMULATIVE NET LOSS RATIO
																		Units (a)			Dollars
{92} Receivables becoming Defaulted Receivables during period																{92}			242			3,646,565.22
{93} Cram Down Losses occurring during period																{93}			3			(67.12	)
{94} Liquidation Proceeds collected during period																{94}			1,596			2,014,178.31
{95} Net losses during period																{95}						1,632,319.79
(a) Unit count represents # of instances in period per line item
															Net Loss for Period			Avg. Portfolio Balance (b)			Net Loss Ratio (c)
{96} Current Period Net Loss Ratio														{96}		1,632,319.79			260,476,744.22			0.63	%
{97} Prior Period Net Loss Ratio														{97}		2,569,246.90			275,113,440.03			0.93	%
{98} Second Prior Period Net Loss Ratio														{98}		2,918,989.28			289,956,416.99			1.01	%
{99} Third Prior Period Net Loss Ratio														{99}		2,988,968.67			304,762,857.15			0.98	%
{100} Rolling 3 prior month average Net Loss Ratio														{100}								0.97	%
(b) Average Portfolio Balance calculated using (Beginning of Period Aggregate Balance + End of Period Aggregate Balance)/2
(c) Net Loss Ratio calculated using Net Loss for Period/Average Portfolio Balance for Period
{101} Cumulative Net losses since Cut-off Date (beginning of period)																			{101}			169,742,831.92
{102} Net losses during period																			{102}			1,632,319.79
{103} Other Adjustments																			{103}			(189,803.97	)
{104} Cumulative Net losses since Cut-off Date (end of period)																			{104}			171,185,347.74
{105} Cumulative Net Loss Ratio (Net losses since the Cut-off Date / Pool Balance as of the Cut-off Date)																			{105}			12.15	%

No assets securitized by Santander Consumer USA Inc. (the “Securitizer”) and held by Santander Drive Auto Receivables Trust 2015-4 were the subject of a demand to repurchase or replace for breach of the representations and warranties during the monthly distribution period from March 1, 2019 to March 31, 2019. Please refer to the Form ABS-15G filed by the Securitizer on January 30, 2019 for additional information. The CIK number of the Securitizer is 0001540151.

IN WITNESS WHEREOF, the undersigned has duly executed and delivered this monthly Statement to Noteholders as dated below.

Santander Consumer USA Inc., as Servicer
By:	/s/ Jason Micheletto
Name:	Jason Micheletto
Title:	Vice President, Corporate Treasury Reporting
Date:	April 8, 2019