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HELOC Calculator

Estimate your interest-only draw period payment and your amortizing repayment period payment on a home equity line of credit (HELOC).

Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.

Your home's current market value, used to figure out your maximum available credit line.
$
What you still owe on your primary mortgage. This reduces the equity available for your credit line.
$
The maximum combined loan-to-value your lender allows across your mortgage and HELOC — commonly 80%-90%.
%
The total revolving credit line your lender approves — you don't have to draw all of it at once.
$
How much of the credit line you'll actually borrow. Interest only accrues on the amount drawn, not the full limit.
$
The years you can borrow and repay funds, typically making interest-only payments. Commonly 5 to 10 years.
yrs
HELOC rates are usually variable, often tied to the prime rate. Enter today's rate for an interest-only draw period estimate.
%
After the draw period ends, the outstanding balance amortizes over this many years. Commonly 10 to 20 years.
yrs
The rate assumed during the amortizing repayment phase — since HELOC rates are variable, you may want to test a higher rate here for a conservative estimate.
%
The date your draw period begins. Used to project your repayment start and payoff dates.

Draw-Period Payment

interest-only

Repayment-Period Payment

principal + interest

Example

Drawing $50,000 from a $50,000 credit line, the interest-only payment during the 10-year draw period at 8.5% is $354.17/month. Once repayment begins in Aug 2036, the balance amortizes over 15 years at 8.5%, for a payment of $492.37/month. Total interest over both phases is about $81,127.

Available Credit Line

Based on your inputs, your lender would typically allow up to $120,000.00 — combined loan-to-value with this full limit drawn is 62.5%.

Amount Drawn

$50,000.00

Total Interest

$81,126.96

Payoff Date

Aug 2051

Total cost, split between principal and each phase's interest

  • Principal: $50,000.00
  • Draw Interest: $42,500.40
  • Repayment Interest: $38,626.56

What is a HELOC Calculator?

A HELOC (home equity line of credit) calculator estimates your payments on a revolving credit line secured by your home's equity — similar to a credit card, but with your house as collateral and typically a far lower interest rate. Unlike a home equity loan's single lump sum, a HELOC lets you draw funds as needed, up to your approved limit, during a set draw period.

This calculator models both phases of a HELOC: the draw period, where you typically make interest-only payments on whatever balance you've drawn, and the repayment period, where the line closes to new draws and the outstanding balance amortizes into fixed principal-and-interest payments — often causing a payment shock if you weren't planning for it.

Remaining balance and cumulative interest across the draw and repayment periods

Full Payment Schedule
Repayment begins: Aug 2036
Month Payment Principal Interest Balance
1 $354.17 $0.00 $354.17 $50,000.00
2 $354.17 $0.00 $354.17 $50,000.00
3 $354.17 $0.00 $354.17 $50,000.00
4 $354.17 $0.00 $354.17 $50,000.00
5 $354.17 $0.00 $354.17 $50,000.00
6 $354.17 $0.00 $354.17 $50,000.00
7 $354.17 $0.00 $354.17 $50,000.00
8 $354.17 $0.00 $354.17 $50,000.00
9 $354.17 $0.00 $354.17 $50,000.00
10 $354.17 $0.00 $354.17 $50,000.00
11 $354.17 $0.00 $354.17 $50,000.00
12 $354.17 $0.00 $354.17 $50,000.00
13 $354.17 $0.00 $354.17 $50,000.00
14 $354.17 $0.00 $354.17 $50,000.00
15 $354.17 $0.00 $354.17 $50,000.00
16 $354.17 $0.00 $354.17 $50,000.00
17 $354.17 $0.00 $354.17 $50,000.00
18 $354.17 $0.00 $354.17 $50,000.00
19 $354.17 $0.00 $354.17 $50,000.00
20 $354.17 $0.00 $354.17 $50,000.00
21 $354.17 $0.00 $354.17 $50,000.00
22 $354.17 $0.00 $354.17 $50,000.00
23 $354.17 $0.00 $354.17 $50,000.00
24 $354.17 $0.00 $354.17 $50,000.00
25 $354.17 $0.00 $354.17 $50,000.00
26 $354.17 $0.00 $354.17 $50,000.00
27 $354.17 $0.00 $354.17 $50,000.00
28 $354.17 $0.00 $354.17 $50,000.00
29 $354.17 $0.00 $354.17 $50,000.00
30 $354.17 $0.00 $354.17 $50,000.00
31 $354.17 $0.00 $354.17 $50,000.00
32 $354.17 $0.00 $354.17 $50,000.00
33 $354.17 $0.00 $354.17 $50,000.00
34 $354.17 $0.00 $354.17 $50,000.00
35 $354.17 $0.00 $354.17 $50,000.00
36 $354.17 $0.00 $354.17 $50,000.00
37 $354.17 $0.00 $354.17 $50,000.00
38 $354.17 $0.00 $354.17 $50,000.00
39 $354.17 $0.00 $354.17 $50,000.00
40 $354.17 $0.00 $354.17 $50,000.00
41 $354.17 $0.00 $354.17 $50,000.00
42 $354.17 $0.00 $354.17 $50,000.00
43 $354.17 $0.00 $354.17 $50,000.00
44 $354.17 $0.00 $354.17 $50,000.00
45 $354.17 $0.00 $354.17 $50,000.00
46 $354.17 $0.00 $354.17 $50,000.00
47 $354.17 $0.00 $354.17 $50,000.00
48 $354.17 $0.00 $354.17 $50,000.00
49 $354.17 $0.00 $354.17 $50,000.00
50 $354.17 $0.00 $354.17 $50,000.00
51 $354.17 $0.00 $354.17 $50,000.00
52 $354.17 $0.00 $354.17 $50,000.00
53 $354.17 $0.00 $354.17 $50,000.00
54 $354.17 $0.00 $354.17 $50,000.00
55 $354.17 $0.00 $354.17 $50,000.00
56 $354.17 $0.00 $354.17 $50,000.00
57 $354.17 $0.00 $354.17 $50,000.00
58 $354.17 $0.00 $354.17 $50,000.00
59 $354.17 $0.00 $354.17 $50,000.00
60 $354.17 $0.00 $354.17 $50,000.00
61 $354.17 $0.00 $354.17 $50,000.00
62 $354.17 $0.00 $354.17 $50,000.00
63 $354.17 $0.00 $354.17 $50,000.00
64 $354.17 $0.00 $354.17 $50,000.00
65 $354.17 $0.00 $354.17 $50,000.00
66 $354.17 $0.00 $354.17 $50,000.00
67 $354.17 $0.00 $354.17 $50,000.00
68 $354.17 $0.00 $354.17 $50,000.00
69 $354.17 $0.00 $354.17 $50,000.00
70 $354.17 $0.00 $354.17 $50,000.00
71 $354.17 $0.00 $354.17 $50,000.00
72 $354.17 $0.00 $354.17 $50,000.00
73 $354.17 $0.00 $354.17 $50,000.00
74 $354.17 $0.00 $354.17 $50,000.00
75 $354.17 $0.00 $354.17 $50,000.00
76 $354.17 $0.00 $354.17 $50,000.00
77 $354.17 $0.00 $354.17 $50,000.00
78 $354.17 $0.00 $354.17 $50,000.00
79 $354.17 $0.00 $354.17 $50,000.00
80 $354.17 $0.00 $354.17 $50,000.00
81 $354.17 $0.00 $354.17 $50,000.00
82 $354.17 $0.00 $354.17 $50,000.00
83 $354.17 $0.00 $354.17 $50,000.00
84 $354.17 $0.00 $354.17 $50,000.00
85 $354.17 $0.00 $354.17 $50,000.00
86 $354.17 $0.00 $354.17 $50,000.00
87 $354.17 $0.00 $354.17 $50,000.00
88 $354.17 $0.00 $354.17 $50,000.00
89 $354.17 $0.00 $354.17 $50,000.00
90 $354.17 $0.00 $354.17 $50,000.00
91 $354.17 $0.00 $354.17 $50,000.00
92 $354.17 $0.00 $354.17 $50,000.00
93 $354.17 $0.00 $354.17 $50,000.00
94 $354.17 $0.00 $354.17 $50,000.00
95 $354.17 $0.00 $354.17 $50,000.00
96 $354.17 $0.00 $354.17 $50,000.00
97 $354.17 $0.00 $354.17 $50,000.00
98 $354.17 $0.00 $354.17 $50,000.00
99 $354.17 $0.00 $354.17 $50,000.00
100 $354.17 $0.00 $354.17 $50,000.00
101 $354.17 $0.00 $354.17 $50,000.00
102 $354.17 $0.00 $354.17 $50,000.00
103 $354.17 $0.00 $354.17 $50,000.00
104 $354.17 $0.00 $354.17 $50,000.00
105 $354.17 $0.00 $354.17 $50,000.00
106 $354.17 $0.00 $354.17 $50,000.00
107 $354.17 $0.00 $354.17 $50,000.00
108 $354.17 $0.00 $354.17 $50,000.00
109 $354.17 $0.00 $354.17 $50,000.00
110 $354.17 $0.00 $354.17 $50,000.00
111 $354.17 $0.00 $354.17 $50,000.00
112 $354.17 $0.00 $354.17 $50,000.00
113 $354.17 $0.00 $354.17 $50,000.00
114 $354.17 $0.00 $354.17 $50,000.00
115 $354.17 $0.00 $354.17 $50,000.00
116 $354.17 $0.00 $354.17 $50,000.00
117 $354.17 $0.00 $354.17 $50,000.00
118 $354.17 $0.00 $354.17 $50,000.00
119 $354.17 $0.00 $354.17 $50,000.00
120 $354.17 $0.00 $354.17 $50,000.00
121 $492.37 $138.20 $354.17 $49,861.80
122 $492.37 $139.18 $353.19 $49,722.61
123 $492.37 $140.17 $352.20 $49,582.45
124 $492.37 $141.16 $351.21 $49,441.29
125 $492.37 $142.16 $350.21 $49,299.13
126 $492.37 $143.17 $349.20 $49,155.96
127 $492.37 $144.18 $348.19 $49,011.78
128 $492.37 $145.20 $347.17 $48,866.57
129 $492.37 $146.23 $346.14 $48,720.34
130 $492.37 $147.27 $345.10 $48,573.07
131 $492.37 $148.31 $344.06 $48,424.76
132 $492.37 $149.36 $343.01 $48,275.40
133 $492.37 $150.42 $341.95 $48,124.98
134 $492.37 $151.48 $340.89 $47,973.50
135 $492.37 $152.56 $339.81 $47,820.94
136 $492.37 $153.64 $338.73 $47,667.30
137 $492.37 $154.73 $337.64 $47,512.58
138 $492.37 $155.82 $336.55 $47,356.75
139 $492.37 $156.93 $335.44 $47,199.83
140 $492.37 $158.04 $334.33 $47,041.79
141 $492.37 $159.16 $333.21 $46,882.63
142 $492.37 $160.28 $332.09 $46,722.35
143 $492.37 $161.42 $330.95 $46,560.93
144 $492.37 $162.56 $329.81 $46,398.37
145 $492.37 $163.71 $328.66 $46,234.65
146 $492.37 $164.87 $327.50 $46,069.78
147 $492.37 $166.04 $326.33 $45,903.74
148 $492.37 $167.22 $325.15 $45,736.52
149 $492.37 $168.40 $323.97 $45,568.11
150 $492.37 $169.60 $322.77 $45,398.52
151 $492.37 $170.80 $321.57 $45,227.72
152 $492.37 $172.01 $320.36 $45,055.71
153 $492.37 $173.23 $319.14 $44,882.49
154 $492.37 $174.45 $317.92 $44,708.04
155 $492.37 $175.69 $316.68 $44,532.35
156 $492.37 $176.93 $315.44 $44,355.42
157 $492.37 $178.19 $314.18 $44,177.23
158 $492.37 $179.45 $312.92 $43,997.78
159 $492.37 $180.72 $311.65 $43,817.07
160 $492.37 $182.00 $310.37 $43,635.07
161 $492.37 $183.29 $309.08 $43,451.78
162 $492.37 $184.59 $307.78 $43,267.19
163 $492.37 $185.89 $306.48 $43,081.30
164 $492.37 $187.21 $305.16 $42,894.09
165 $492.37 $188.54 $303.83 $42,705.55
166 $492.37 $189.87 $302.50 $42,515.68
167 $492.37 $191.22 $301.15 $42,324.46
168 $492.37 $192.57 $299.80 $42,131.89
169 $492.37 $193.94 $298.43 $41,937.95
170 $492.37 $195.31 $297.06 $41,742.65
171 $492.37 $196.69 $295.68 $41,545.95
172 $492.37 $198.09 $294.28 $41,347.87
173 $492.37 $199.49 $292.88 $41,148.38
174 $492.37 $200.90 $291.47 $40,947.48
175 $492.37 $202.33 $290.04 $40,745.15
176 $492.37 $203.76 $288.61 $40,541.39
177 $492.37 $205.20 $287.17 $40,336.19
178 $492.37 $206.66 $285.71 $40,129.54
179 $492.37 $208.12 $284.25 $39,921.42
180 $492.37 $209.59 $282.78 $39,711.82
181 $492.37 $211.08 $281.29 $39,500.75
182 $492.37 $212.57 $279.80 $39,288.17
183 $492.37 $214.08 $278.29 $39,074.09
184 $492.37 $215.59 $276.77 $38,858.50
185 $492.37 $217.12 $275.25 $38,641.38
186 $492.37 $218.66 $273.71 $38,422.72
187 $492.37 $220.21 $272.16 $38,202.51
188 $492.37 $221.77 $270.60 $37,980.74
189 $492.37 $223.34 $269.03 $37,757.40
190 $492.37 $224.92 $267.45 $37,532.48
191 $492.37 $226.51 $265.86 $37,305.96
192 $492.37 $228.12 $264.25 $37,077.84
193 $492.37 $229.74 $262.63 $36,848.11
194 $492.37 $231.36 $261.01 $36,616.75
195 $492.37 $233.00 $259.37 $36,383.75
196 $492.37 $234.65 $257.72 $36,149.09
197 $492.37 $236.31 $256.06 $35,912.78
198 $492.37 $237.99 $254.38 $35,674.79
199 $492.37 $239.67 $252.70 $35,435.12
200 $492.37 $241.37 $251.00 $35,193.75
201 $492.37 $243.08 $249.29 $34,950.67
202 $492.37 $244.80 $247.57 $34,705.87
203 $492.37 $246.54 $245.83 $34,459.33
204 $492.37 $248.28 $244.09 $34,211.05
205 $492.37 $250.04 $242.33 $33,961.00
206 $492.37 $251.81 $240.56 $33,709.19
207 $492.37 $253.60 $238.77 $33,455.60
208 $492.37 $255.39 $236.98 $33,200.20
209 $492.37 $257.20 $235.17 $32,943.00
210 $492.37 $259.02 $233.35 $32,683.98
211 $492.37 $260.86 $231.51 $32,423.12
212 $492.37 $262.71 $229.66 $32,160.41
213 $492.37 $264.57 $227.80 $31,895.85
214 $492.37 $266.44 $225.93 $31,629.41
215 $492.37 $268.33 $224.04 $31,361.08
216 $492.37 $270.23 $222.14 $31,090.85
217 $492.37 $272.14 $220.23 $30,818.71
218 $492.37 $274.07 $218.30 $30,544.64
219 $492.37 $276.01 $216.36 $30,268.62
220 $492.37 $277.97 $214.40 $29,990.66
221 $492.37 $279.94 $212.43 $29,710.72
222 $492.37 $281.92 $210.45 $29,428.80
223 $492.37 $283.92 $208.45 $29,144.89
224 $492.37 $285.93 $206.44 $28,858.96
225 $492.37 $287.95 $204.42 $28,571.01
226 $492.37 $289.99 $202.38 $28,281.02
227 $492.37 $292.05 $200.32 $27,988.97
228 $492.37 $294.11 $198.26 $27,694.85
229 $492.37 $296.20 $196.17 $27,398.66
230 $492.37 $298.30 $194.07 $27,100.36
231 $492.37 $300.41 $191.96 $26,799.95
232 $492.37 $302.54 $189.83 $26,497.42
233 $492.37 $304.68 $187.69 $26,192.74
234 $492.37 $306.84 $185.53 $25,885.90
235 $492.37 $309.01 $183.36 $25,576.89
236 $492.37 $311.20 $181.17 $25,265.69
237 $492.37 $313.40 $178.97 $24,952.28
238 $492.37 $315.62 $176.75 $24,636.66
239 $492.37 $317.86 $174.51 $24,318.80
240 $492.37 $320.11 $172.26 $23,998.69
241 $492.37 $322.38 $169.99 $23,676.31
242 $492.37 $324.66 $167.71 $23,351.64
243 $492.37 $326.96 $165.41 $23,024.68
244 $492.37 $329.28 $163.09 $22,695.40
245 $492.37 $331.61 $160.76 $22,363.79
246 $492.37 $333.96 $158.41 $22,029.83
247 $492.37 $336.33 $156.04 $21,693.51
248 $492.37 $338.71 $153.66 $21,354.80
249 $492.37 $341.11 $151.26 $21,013.69
250 $492.37 $343.52 $148.85 $20,670.17
251 $492.37 $345.96 $146.41 $20,324.21
252 $492.37 $348.41 $143.96 $19,975.81
253 $492.37 $350.87 $141.50 $19,624.93
254 $492.37 $353.36 $139.01 $19,271.57
255 $492.37 $355.86 $136.51 $18,915.71
256 $492.37 $358.38 $133.99 $18,557.33
257 $492.37 $360.92 $131.45 $18,196.41
258 $492.37 $363.48 $128.89 $17,832.93
259 $492.37 $366.05 $126.32 $17,466.87
260 $492.37 $368.65 $123.72 $17,098.23
261 $492.37 $371.26 $121.11 $16,726.97
262 $492.37 $373.89 $118.48 $16,353.08
263 $492.37 $376.54 $115.83 $15,976.55
264 $492.37 $379.20 $113.17 $15,597.35
265 $492.37 $381.89 $110.48 $15,215.46
266 $492.37 $384.59 $107.78 $14,830.86
267 $492.37 $387.32 $105.05 $14,443.55
268 $492.37 $390.06 $102.31 $14,053.48
269 $492.37 $392.82 $99.55 $13,660.66
270 $492.37 $395.61 $96.76 $13,265.05
271 $492.37 $398.41 $93.96 $12,866.64
272 $492.37 $401.23 $91.14 $12,465.41
273 $492.37 $404.07 $88.30 $12,061.34
274 $492.37 $406.94 $85.43 $11,654.40
275 $492.37 $409.82 $82.55 $11,244.59
276 $492.37 $412.72 $79.65 $10,831.87
277 $492.37 $415.64 $76.73 $10,416.22
278 $492.37 $418.59 $73.78 $9,997.63
279 $492.37 $421.55 $70.82 $9,576.08
280 $492.37 $424.54 $67.83 $9,151.54
281 $492.37 $427.55 $64.82 $8,723.99
282 $492.37 $430.57 $61.79 $8,293.42
283 $492.37 $433.62 $58.75 $7,859.80
284 $492.37 $436.70 $55.67 $7,423.10
285 $492.37 $439.79 $52.58 $6,983.31
286 $492.37 $442.90 $49.47 $6,540.41
287 $492.37 $446.04 $46.33 $6,094.36
288 $492.37 $449.20 $43.17 $5,645.16
289 $492.37 $452.38 $39.99 $5,192.78
290 $492.37 $455.59 $36.78 $4,737.19
291 $492.37 $458.81 $33.56 $4,278.38
292 $492.37 $462.06 $30.31 $3,816.31
293 $492.37 $465.34 $27.03 $3,350.97
294 $492.37 $468.63 $23.74 $2,882.34
295 $492.37 $471.95 $20.42 $2,410.39
296 $492.37 $475.30 $17.07 $1,935.09
297 $492.37 $478.66 $13.71 $1,456.43
298 $492.37 $482.05 $10.32 $974.37
299 $492.37 $485.47 $6.90 $488.91
300 $492.37 $488.91 $3.46 $0.00

How HELOC Payments Are Calculated

During the draw period, most HELOCs charge interest-only payments on the drawn balance — the principal doesn't go down unless you voluntarily pay more than the minimum. The formula is simple:

Draw Payment = Balance × (Annual Rate ÷ 12)

Once the draw period ends, the line converts to a standard amortizing loan over the repayment period, using the same formula as a mortgage or home equity loan:

M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]
  • M — repayment-period monthly payment
  • P — balance outstanding when the draw period ends
  • r — monthly interest rate during repayment
  • n — number of repayment-period months

The "Payment Shock" at the End of the Draw Period

The single biggest risk with a HELOC is underestimating how much the payment jumps once the draw period ends. Paying only interest on $50,000 at 8.5% costs about $354/month — but amortizing that same $50,000 over 15 years at 8.5% costs about $492/month, a roughly 39% increase, even before accounting for any rate changes. Borrowers who plan to carry a balance into the repayment period should budget for this jump well in advance.

Variable Rates and Combined Loan-to-Value

Almost all HELOCs carry a variable interest rate, usually the prime rate plus a margin that depends on your credit profile — so your actual payment can rise or fall over time in ways this calculator (which assumes a fixed rate for simplicity) cannot predict. Lenders also cap how large your credit line can be using combined loan-to-value (CLTV): existing mortgage balance plus the new credit line, divided by your home's value, commonly capped at 80% to 90%.

HELOC vs. Home Equity Loan

A HELOC works best for ongoing or uncertain expenses — home renovations spread over time, tuition paid annually, or an emergency fund you hope not to use — because you only pay interest on what you actually draw. A home equity loan is better when you know the exact amount you need up front and want the payment certainty of a fixed rate from day one.

Example — Your Current Inputs

Drawing $50,000 from a $50,000 credit line, the interest-only payment during the 10-year draw period at 8.5% is $354.17/month. Once repayment begins in Aug 2036, the balance amortizes over 15 years at 8.5%, for a payment of $492.37/month. Total interest over both phases is about $81,127.

Additional Example — Home Renovation

A homeowner opens a $75,000 HELOC to renovate their kitchen in phases over several years, ultimately drawing $60,000. During the 10-year draw period at 8.5%, the interest-only payment is about $425/month. When the 15-year repayment period begins, the payment rises to about $591/month as the balance starts amortizing — a jump worth planning for years in advance.

About These Parameters

Home's Current Value & Existing Mortgage Balance
Together with your lender's max combined LTV, these determine how large a credit line you can typically qualify for.
Credit Line Limit vs. Amount Drawn
The limit is the maximum you're approved to borrow; the amount drawn is what you actually withdraw and pay interest on. These can differ — many borrowers open a larger line than they immediately use.
Draw Period & Draw-Period Rate
The years you can borrow and repay funds, usually with interest-only minimum payments. Commonly 5 to 10 years, at a variable rate.
Repayment Period & Repayment-Period Rate
Once the draw period closes, the outstanding balance amortizes over this many years. Since rates are variable, consider testing a higher repayment-period rate for a conservative estimate.

Frequently Asked Questions

What happens when the HELOC draw period ends?

The line closes to further draws, and whatever balance remains begins amortizing into fixed principal-and-interest payments over the repayment period — typically causing a noticeable payment increase compared to the interest-only draw period.

Is HELOC interest tax-deductible?

In the US, it can be, but only when funds are used to "buy, build, or substantially improve" the home securing the line — not for other purposes like debt consolidation or tuition. Consult a tax professional about your specific situation.

Can I pay down and re-borrow during the draw period?

Yes — that's the defining feature of a HELOC. Like a credit card, paying down the balance during the draw period frees up available credit you can draw again, up to your approved limit.

Why is my HELOC rate variable?

Most HELOCs are priced as the prime rate plus a margin set by your credit profile, so your payment can rise or fall as the prime rate moves — unlike a fixed-rate home equity loan. Some lenders offer a fixed-rate conversion option on part of the balance.

See also