How much interest does a 30-year mortgage cost?

On a $300,000 mortgage at 6.5%, total payments over 30 years exceed $680,000 — more than double the original loan amount.

How much can extra payments save?

Even $100-200 extra per month on a 30-year mortgage can save tens of thousands in interest and cut years off the loan term.

Loan Amortization Calculator

Q: What is loan amortization?

Amortization is paying off a loan through regular scheduled payments. Early payments are mostly interest; later payments shift toward principal.

Calculate monthly payments, total interest, and see a full amortization schedule. See exactly how extra payments save you money.

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Parameters

Calculate your loan schedule

Loan Amount

$1,000$2,000,000

Annual Interest Rate

0.1%20%

Loan Term

yrs

1 yrs30 yrs

Extra Monthly Payment

$0$5,000

Monthly Payment

$ 0

Standard 30-year term

Total Payment

$ 0

Total Interest

$ 0

Interest Saved

$ 0

Time Saved

0 yrs

Payment Breakdown

Principal 44%Interest 56%

Loan Balance Over Time

Remaining balance and annual payments

Principal vs Interest Per Year

How each payment is split over time

Amortization Schedule

Month-by-month payment breakdown

Month	Payment	Principal	Interest	Balance
1	$1,896	$271	$1,625	$299,729
2	$1,896	$273	$1,624	$299,456
3	$1,896	$274	$1,622	$299,182
4	$1,896	$276	$1,621	$298,906
5	$1,896	$277	$1,619	$298,629
6	$1,896	$279	$1,618	$298,351
7	$1,896	$280	$1,616	$298,070
8	$1,896	$282	$1,615	$297,789
9	$1,896	$283	$1,613	$297,506
10	$1,896	$285	$1,611	$297,221
11	$1,896	$286	$1,610	$296,935
12	$1,896	$288	$1,608	$296,647
13	$1,896	$289	$1,607	$296,358
14	$1,896	$291	$1,605	$296,067
15	$1,896	$293	$1,604	$295,774
16	$1,896	$294	$1,602	$295,480
17	$1,896	$296	$1,601	$295,184
18	$1,896	$297	$1,599	$294,887
19	$1,896	$299	$1,597	$294,588
20	$1,896	$301	$1,596	$294,288
21	$1,896	$302	$1,594	$293,985
22	$1,896	$304	$1,592	$293,682
23	$1,896	$305	$1,591	$293,376
24	$1,896	$307	$1,589	$293,069
25	$1,896	$309	$1,587	$292,760
26	$1,896	$310	$1,586	$292,450
27	$1,896	$312	$1,584	$292,138
28	$1,896	$314	$1,582	$291,824
29	$1,896	$315	$1,581	$291,509
30	$1,896	$317	$1,579	$291,191
31	$1,896	$319	$1,577	$290,873
32	$1,896	$321	$1,576	$290,552
33	$1,896	$322	$1,574	$290,230
34	$1,896	$324	$1,572	$289,905
35	$1,896	$326	$1,570	$289,580
36	$1,896	$328	$1,569	$289,252
37	$1,896	$329	$1,567	$288,922
38	$1,896	$331	$1,565	$288,591
39	$1,896	$333	$1,563	$288,258
40	$1,896	$335	$1,561	$287,923
41	$1,896	$337	$1,560	$287,587
42	$1,896	$338	$1,558	$287,248
43	$1,896	$340	$1,556	$286,908
44	$1,896	$342	$1,554	$286,566
45	$1,896	$344	$1,552	$286,222
46	$1,896	$346	$1,550	$285,876
47	$1,896	$348	$1,549	$285,529
48	$1,896	$350	$1,547	$285,179
49	$1,896	$351	$1,545	$284,827
50	$1,896	$353	$1,543	$284,474
51	$1,896	$355	$1,541	$284,119
52	$1,896	$357	$1,539	$283,762
53	$1,896	$359	$1,537	$283,402
54	$1,896	$361	$1,535	$283,041
55	$1,896	$363	$1,533	$282,678
56	$1,896	$365	$1,531	$282,313
57	$1,896	$367	$1,529	$281,946
58	$1,896	$369	$1,527	$281,577
59	$1,896	$371	$1,525	$281,206
60	$1,896	$373	$1,523	$280,833
61	$1,896	$375	$1,521	$280,458
62	$1,896	$377	$1,519	$280,081
63	$1,896	$379	$1,517	$279,702
64	$1,896	$381	$1,515	$279,321
65	$1,896	$383	$1,513	$278,938
66	$1,896	$385	$1,511	$278,552
67	$1,896	$387	$1,509	$278,165
68	$1,896	$389	$1,507	$277,776
69	$1,896	$392	$1,505	$277,384
70	$1,896	$394	$1,503	$276,990
71	$1,896	$396	$1,500	$276,594
72	$1,896	$398	$1,498	$276,197
73	$1,896	$400	$1,496	$275,796
74	$1,896	$402	$1,494	$275,394
75	$1,896	$404	$1,492	$274,990
76	$1,896	$407	$1,490	$274,583
77	$1,896	$409	$1,487	$274,174
78	$1,896	$411	$1,485	$273,763
79	$1,896	$413	$1,483	$273,350
80	$1,896	$416	$1,481	$272,934
81	$1,896	$418	$1,478	$272,516
82	$1,896	$420	$1,476	$272,096
83	$1,896	$422	$1,474	$271,674
84	$1,896	$425	$1,472	$271,249
85	$1,896	$427	$1,469	$270,822
86	$1,896	$429	$1,467	$270,393
87	$1,896	$432	$1,465	$269,961
88	$1,896	$434	$1,462	$269,528
89	$1,896	$436	$1,460	$269,091
90	$1,896	$439	$1,458	$268,653
91	$1,896	$441	$1,455	$268,212
92	$1,896	$443	$1,453	$267,768
93	$1,896	$446	$1,450	$267,322
94	$1,896	$448	$1,448	$266,874
95	$1,896	$451	$1,446	$266,424
96	$1,896	$453	$1,443	$265,971
97	$1,896	$456	$1,441	$265,515
98	$1,896	$458	$1,438	$265,057
99	$1,896	$460	$1,436	$264,597
100	$1,896	$463	$1,433	$264,134
101	$1,896	$465	$1,431	$263,668
102	$1,896	$468	$1,428	$263,200
103	$1,896	$471	$1,426	$262,730
104	$1,896	$473	$1,423	$262,257
105	$1,896	$476	$1,421	$261,781
106	$1,896	$478	$1,418	$261,303
107	$1,896	$481	$1,415	$260,822
108	$1,896	$483	$1,413	$260,338
109	$1,896	$486	$1,410	$259,852
110	$1,896	$489	$1,408	$259,364
111	$1,896	$491	$1,405	$258,872
112	$1,896	$494	$1,402	$258,378
113	$1,896	$497	$1,400	$257,882
114	$1,896	$499	$1,397	$257,382
115	$1,896	$502	$1,394	$256,880
116	$1,896	$505	$1,391	$256,376
117	$1,896	$508	$1,389	$255,868
118	$1,896	$510	$1,386	$255,358
119	$1,896	$513	$1,383	$254,845
120	$1,896	$516	$1,380	$254,329
121	$1,896	$519	$1,378	$253,811
122	$1,896	$521	$1,375	$253,289
123	$1,896	$524	$1,372	$252,765
124	$1,896	$527	$1,369	$252,238
125	$1,896	$530	$1,366	$251,708
126	$1,896	$533	$1,363	$251,175
127	$1,896	$536	$1,361	$250,640
128	$1,896	$539	$1,358	$250,101
129	$1,896	$541	$1,355	$249,559
130	$1,896	$544	$1,352	$249,015
131	$1,896	$547	$1,349	$248,468
132	$1,896	$550	$1,346	$247,917
133	$1,896	$553	$1,343	$247,364
134	$1,896	$556	$1,340	$246,808
135	$1,896	$559	$1,337	$246,248
136	$1,896	$562	$1,334	$245,686
137	$1,896	$565	$1,331	$245,121
138	$1,896	$568	$1,328	$244,552
139	$1,896	$572	$1,325	$243,981
140	$1,896	$575	$1,322	$243,406
141	$1,896	$578	$1,318	$242,828
142	$1,896	$581	$1,315	$242,247
143	$1,896	$584	$1,312	$241,663
144	$1,896	$587	$1,309	$241,076
145	$1,896	$590	$1,306	$240,486
146	$1,896	$594	$1,303	$239,892
147	$1,896	$597	$1,299	$239,295
148	$1,896	$600	$1,296	$238,695
149	$1,896	$603	$1,293	$238,092
150	$1,896	$607	$1,290	$237,486
151	$1,896	$610	$1,286	$236,876
152	$1,896	$613	$1,283	$236,263
153	$1,896	$616	$1,280	$235,646
154	$1,896	$620	$1,276	$235,026
155	$1,896	$623	$1,273	$234,403
156	$1,896	$627	$1,270	$233,777
157	$1,896	$630	$1,266	$233,147
158	$1,896	$633	$1,263	$232,514
159	$1,896	$637	$1,259	$231,877
160	$1,896	$640	$1,256	$231,237
161	$1,896	$644	$1,253	$230,593
162	$1,896	$647	$1,249	$229,946
163	$1,896	$651	$1,246	$229,295
164	$1,896	$654	$1,242	$228,641
165	$1,896	$658	$1,238	$227,983
166	$1,896	$661	$1,235	$227,322
167	$1,896	$665	$1,231	$226,657
168	$1,896	$668	$1,228	$225,989
169	$1,896	$672	$1,224	$225,317
170	$1,896	$676	$1,220	$224,641
171	$1,896	$679	$1,217	$223,961
172	$1,896	$683	$1,213	$223,278
173	$1,896	$687	$1,209	$222,592
174	$1,896	$691	$1,206	$221,901
175	$1,896	$694	$1,202	$221,207
176	$1,896	$698	$1,198	$220,509
177	$1,896	$702	$1,194	$219,807
178	$1,896	$706	$1,191	$219,101
179	$1,896	$709	$1,187	$218,392
180	$1,896	$713	$1,183	$217,679
181	$1,896	$717	$1,179	$216,962
182	$1,896	$721	$1,175	$216,241
183	$1,896	$725	$1,171	$215,516
184	$1,896	$729	$1,167	$214,787
185	$1,896	$733	$1,163	$214,054
186	$1,896	$737	$1,159	$213,317
187	$1,896	$741	$1,155	$212,577
188	$1,896	$745	$1,151	$211,832
189	$1,896	$749	$1,147	$211,083
190	$1,896	$753	$1,143	$210,330
191	$1,896	$757	$1,139	$209,573
192	$1,896	$761	$1,135	$208,812
193	$1,896	$765	$1,131	$208,047
194	$1,896	$769	$1,127	$207,278
195	$1,896	$773	$1,123	$206,505
196	$1,896	$778	$1,119	$205,727
197	$1,896	$782	$1,114	$204,945
198	$1,896	$786	$1,110	$204,159
199	$1,896	$790	$1,106	$203,369
200	$1,896	$795	$1,102	$202,574
201	$1,896	$799	$1,097	$201,775
202	$1,896	$803	$1,093	$200,972
203	$1,896	$808	$1,089	$200,164
204	$1,896	$812	$1,084	$199,352
205	$1,896	$816	$1,080	$198,536
206	$1,896	$821	$1,075	$197,715
207	$1,896	$825	$1,071	$196,890
208	$1,896	$830	$1,066	$196,060
209	$1,896	$834	$1,062	$195,226
210	$1,896	$839	$1,057	$194,387
211	$1,896	$843	$1,053	$193,544
212	$1,896	$848	$1,048	$192,696
213	$1,896	$852	$1,044	$191,844
214	$1,896	$857	$1,039	$190,987
215	$1,896	$862	$1,035	$190,125
216	$1,896	$866	$1,030	$189,259
217	$1,896	$871	$1,025	$188,388
218	$1,896	$876	$1,020	$187,512
219	$1,896	$881	$1,016	$186,631
220	$1,896	$885	$1,011	$185,746
221	$1,896	$890	$1,006	$184,856
222	$1,896	$895	$1,001	$183,961
223	$1,896	$900	$996	$183,061
224	$1,896	$905	$992	$182,157
225	$1,896	$910	$987	$181,247
226	$1,896	$914	$982	$180,333
227	$1,896	$919	$977	$179,413
228	$1,896	$924	$972	$178,489
229	$1,896	$929	$967	$177,560
230	$1,896	$934	$962	$176,625
231	$1,896	$939	$957	$175,686
232	$1,896	$945	$952	$174,741
233	$1,896	$950	$947	$173,791
234	$1,896	$955	$941	$172,837
235	$1,896	$960	$936	$171,877
236	$1,896	$965	$931	$170,911
237	$1,896	$970	$926	$169,941
238	$1,896	$976	$921	$168,965
239	$1,896	$981	$915	$167,984
240	$1,896	$986	$910	$166,998
241	$1,896	$992	$905	$166,006
242	$1,896	$997	$899	$165,009
243	$1,896	$1,002	$894	$164,007
244	$1,896	$1,008	$888	$162,999
245	$1,896	$1,013	$883	$161,986
246	$1,896	$1,019	$877	$160,967
247	$1,896	$1,024	$872	$159,943
248	$1,896	$1,030	$866	$158,913
249	$1,896	$1,035	$861	$157,877
250	$1,896	$1,041	$855	$156,836
251	$1,896	$1,047	$850	$155,790
252	$1,896	$1,052	$844	$154,737
253	$1,896	$1,058	$838	$153,679
254	$1,896	$1,064	$832	$152,616
255	$1,896	$1,070	$827	$151,546
256	$1,896	$1,075	$821	$150,471
257	$1,896	$1,081	$815	$149,390
258	$1,896	$1,087	$809	$148,303
259	$1,896	$1,093	$803	$147,210
260	$1,896	$1,099	$797	$146,111
261	$1,896	$1,105	$791	$145,006
262	$1,896	$1,111	$785	$143,895
263	$1,896	$1,117	$779	$142,779
264	$1,896	$1,123	$773	$141,656
265	$1,896	$1,129	$767	$140,527
266	$1,896	$1,135	$761	$139,392
267	$1,896	$1,141	$755	$138,251
268	$1,896	$1,147	$749	$137,103
269	$1,896	$1,154	$743	$135,950
270	$1,896	$1,160	$736	$134,790
271	$1,896	$1,166	$730	$133,624
272	$1,896	$1,172	$724	$132,452
273	$1,896	$1,179	$717	$131,273
274	$1,896	$1,185	$711	$130,088
275	$1,896	$1,192	$705	$128,896
276	$1,896	$1,198	$698	$127,698
277	$1,896	$1,205	$692	$126,494
278	$1,896	$1,211	$685	$125,283
279	$1,896	$1,218	$679	$124,065
280	$1,896	$1,224	$672	$122,841
281	$1,896	$1,231	$665	$121,610
282	$1,896	$1,237	$659	$120,372
283	$1,896	$1,244	$652	$119,128
284	$1,896	$1,251	$645	$117,877
285	$1,896	$1,258	$639	$116,620
286	$1,896	$1,265	$632	$115,355
287	$1,896	$1,271	$625	$114,084
288	$1,896	$1,278	$618	$112,806
289	$1,896	$1,285	$611	$111,520
290	$1,896	$1,292	$604	$110,228
291	$1,896	$1,299	$597	$108,929
292	$1,896	$1,306	$590	$107,623
293	$1,896	$1,313	$583	$106,310
294	$1,896	$1,320	$576	$104,989
295	$1,896	$1,328	$569	$103,662
296	$1,896	$1,335	$562	$102,327
297	$1,896	$1,342	$554	$100,985
298	$1,896	$1,349	$547	$99,636
299	$1,896	$1,357	$540	$98,280
300	$1,896	$1,364	$532	$96,916
301	$1,896	$1,371	$525	$95,544
302	$1,896	$1,379	$518	$94,166
303	$1,896	$1,386	$510	$92,780
304	$1,896	$1,394	$503	$91,386
305	$1,896	$1,401	$495	$89,985
306	$1,896	$1,409	$487	$88,576
307	$1,896	$1,416	$480	$87,160
308	$1,896	$1,424	$472	$85,736
309	$1,896	$1,432	$464	$84,304
310	$1,896	$1,440	$457	$82,864
311	$1,896	$1,447	$449	$81,417
312	$1,896	$1,455	$441	$79,962
313	$1,896	$1,463	$433	$78,499
314	$1,896	$1,471	$425	$77,028
315	$1,896	$1,479	$417	$75,549
316	$1,896	$1,487	$409	$74,062
317	$1,896	$1,495	$401	$72,567
318	$1,896	$1,503	$393	$71,063
319	$1,896	$1,511	$385	$69,552
320	$1,896	$1,519	$377	$68,033
321	$1,896	$1,528	$369	$66,505
322	$1,896	$1,536	$360	$64,969
323	$1,896	$1,544	$352	$63,425
324	$1,896	$1,553	$344	$61,872
325	$1,896	$1,561	$335	$60,311
326	$1,896	$1,570	$327	$58,742
327	$1,896	$1,578	$318	$57,164
328	$1,896	$1,587	$310	$55,577
329	$1,896	$1,595	$301	$53,982
330	$1,896	$1,604	$292	$52,378
331	$1,896	$1,612	$284	$50,766
332	$1,896	$1,621	$275	$49,144
333	$1,896	$1,630	$266	$47,514
334	$1,896	$1,639	$257	$45,875
335	$1,896	$1,648	$248	$44,228
336	$1,896	$1,657	$240	$42,571
337	$1,896	$1,666	$231	$40,906
338	$1,896	$1,675	$222	$39,231
339	$1,896	$1,684	$213	$37,547
340	$1,896	$1,693	$203	$35,854
341	$1,896	$1,702	$194	$34,152
342	$1,896	$1,711	$185	$32,441
343	$1,896	$1,720	$176	$30,721
344	$1,896	$1,730	$166	$28,991
345	$1,896	$1,739	$157	$27,252
346	$1,896	$1,749	$148	$25,503
347	$1,896	$1,758	$138	$23,745
348	$1,896	$1,768	$129	$21,978
349	$1,896	$1,777	$119	$20,200
350	$1,896	$1,787	$109	$18,414
351	$1,896	$1,796	$100	$16,617
352	$1,896	$1,806	$90	$14,811
353	$1,896	$1,816	$80	$12,995
354	$1,896	$1,826	$70	$11,169
355	$1,896	$1,836	$61	$9,333
356	$1,896	$1,846	$51	$7,488
357	$1,896	$1,856	$41	$5,632
358	$1,896	$1,866	$31	$3,766
359	$1,896	$1,876	$20	$1,891
360	$1,896	$1,886	$10	$5

* Based on a fixed rate of 6.5% annually. Extra payments not reflected in this schedule.

Results are for informational purposes only and do not constitute financial advice. Actual returns may vary due to market conditions, taxes, and fees. Read our full disclaimer.

What is Loan Amortization?

Loan amortization is the process of paying off a debt through a series of fixed, scheduled payments over a set period of time. Each payment is split into two components: a portion that covers the interest accrued since the last payment, and a portion that reduces the outstanding principal balance. The defining characteristic of an amortizing loan is that the total monthly payment stays constant, but the split between interest and principal shifts dramatically over the loan's life.

In the early months of a loan, the outstanding balance is at its highest, so interest charges consume the majority of each payment. As the balance gradually decreases, less interest accrues each month — meaning more of each fixed payment goes toward principal. By the final months of a 30-year mortgage, nearly the entire payment is principal repayment. This gradual shift is the mechanics of amortization in action.

The Loan Amortization Formula

The standard formula for calculating the fixed monthly payment on an amortizing loan is:

M = P × [r(1+r)^n] / [(1+r)^n - 1]

MMonthly Payment

The fixed amount paid each month (principal + interest)

PPrincipal

The original loan amount borrowed

rMonthly Rate

Annual interest rate divided by 12 (e.g. 6% annual = 0.005 monthly)

nNumber of Payments

Total months of the loan (30 years = 360 payments)

Step-by-Step Calculation Example

Let's calculate the monthly payment and first three months of an amortization schedule for a $300,000 mortgage at 6.5% annual interest over 30 years.

Convert annual rate to monthly

r = 6.5% / 12 = 0.5417% = 0.005417 per month

Calculate total number of payments

n = 30 years × 12 months = 360 payments

Apply the formula

M = $300,000 × [0.005417 × (1.005417)^360] / [(1.005417)^360 - 1] = $1,896.20 per month

Month 1 breakdown

Interest: $300,000 × 0.005417 = $1,625.10 · Principal: $1,896.20 - $1,625.10 = $271.10 · Remaining: $299,728.90

Month 2 breakdown

Interest: $299,728.90 × 0.005417 = $1,623.63 · Principal: $1,896.20 - $1,623.63 = $272.57 · Remaining: $299,456.33

Month 360 (final)

At month 360, nearly the entire $1,896.20 goes to principal. Interest is only about $10. Balance reaches $0.

The True Cost of a Mortgage: What You Actually Pay

The table below shows the total interest paid on a $300,000 loan across different interest rates and loan terms. The numbers are often shocking to first-time borrowers.

Rate	Term	Monthly Payment	Total Interest	Total Paid
5.0%	15 yr	$2,372	$126,960	$426,960
5.0%	30 yr	$1,610	$279,767	$579,767
6.5%	15 yr	$2,614	$170,523	$470,523
6.5%	30 yr	$1,896	$382,633	$682,633
7.5%	15 yr	$2,780	$200,416	$500,416
7.5%	30 yr	$2,098	$455,089	$755,089

* Based on $300,000 principal. Taxes, insurance, and PMI not included.

The most important insight from this table: a 15-year mortgage at 6.5% costs $170,523 in total interest. The 30-year version at the same rate costs $382,633 — more than double. You pay an extra $212,000 for the convenience of lower monthly payments. Whether that trade-off is worth it depends entirely on your financial situation and what you do with the monthly payment difference.

The Power of Extra Payments

Extra payments are one of the highest-return financial moves available to homeowners because they directly reduce the principal balance that all future interest is calculated on. The earlier in the loan you make extra payments, the more dramatically they affect total interest paid.

Extra Payment	Payoff Time	Interest Saved	Years Saved
$0/month (standard)	30 yr 0 mo	$0	0
$100/month	25 yr 8 mo	$47,632	4.3
$200/month	22 yr 6 mo	$78,954	7.5
$500/month	17 yr 3 mo	$135,289	12.8
$1,000/month	12 yr 10 mo	$191,217	17.2

* Based on $300,000 at 6.5% over 30 years.

Adding just $200 per month to a standard 30-year mortgage saves nearly $79,000 in interest and cuts 7.5 years off the loan. The guaranteed return on this "investment" equals your mortgage interest rate — which at 6.5% beats most savings accounts and bonds. The trade-off: this money becomes illiquid (tied up in home equity) and unavailable for investment opportunities.

15-Year vs 30-Year Mortgage: Which is Right for You?

Choose 15-Year if...

✓You can comfortably afford the higher monthly payment
✓You want to minimize total interest paid
✓You are approaching retirement and want to be debt-free
✓You have a stable, predictable income
✓Interest rates are high and you want to pay it off faster

Choose 30-Year if...

✓Cash flow flexibility is a priority (lower monthly payment)
✓You plan to invest the monthly payment difference aggressively
✓Your income is variable or uncertain
✓You expect to sell or refinance within 10 years
✓You have high-interest debt to pay off first

The mathematically optimal answer depends on whether your alternative investment return exceeds your mortgage rate. At a 6.5% mortgage rate, if you can reliably earn more than 6.5% after tax by investing, the 30-year mortgage and investing the difference wins. If not — or if the psychological security of owning your home outright matters to you — the 15-year wins. Neither answer is universally correct.

Common Amortization Mistakes to Avoid

Only comparing monthly payments, not total cost

A lower monthly payment feels like a better deal, but extending from a 15-year to a 30-year mortgage on a $300,000 loan at 6.5% adds over $212,000 in total interest. Always compare total cost of borrowing, not just the monthly number.

Not specifying that extra payments go to principal

Some lenders apply extra payments to future scheduled payments (which does not reduce principal immediately) rather than directly to the current principal balance. Always specify in writing that extra payments should be applied to principal reduction.

Ignoring the opportunity cost of early payoff

Paying off a 3% mortgage early is mathematically equivalent to earning a guaranteed 3% return. If you can earn more in a diversified investment portfolio, investing the extra money may produce better outcomes — depending on your tax situation and risk tolerance.

Refinancing without calculating the break-even point

Refinancing to a lower rate costs money in closing fees (typically 2-5% of the loan). Divide your total closing costs by your monthly savings to find how many months until you break even. If you plan to sell before break-even, refinancing costs more than it saves.

Frequently Asked Questions

Why do I pay so much interest in the early years of my mortgage?

Because your outstanding balance is at its highest. Interest is calculated as a percentage of the remaining balance, so the highest balance produces the highest interest charge. As you pay down principal over time, each month's interest charge decreases slightly.

What happens to my amortization schedule if I make one extra payment per year?

On a 30-year mortgage, making one extra full payment per year typically reduces the loan term by 4-6 years and saves tens of thousands in interest, depending on your rate. The extra payment directly reduces principal, shifting all subsequent interest calculations to a lower base.

How does refinancing affect my amortization?

Refinancing replaces your current loan with a new one, restarting the amortization clock. Even if your new rate is lower, the new loan is front-loaded with interest again. Refinancing from year 20 of a 30-year mortgage to a new 30-year mortgage extends your total payment period and may not save money overall.

Is it better to make biweekly payments instead of monthly?

Biweekly payments result in 26 half-payments per year, equivalent to 13 full monthly payments instead of 12. This extra payment per year reduces a 30-year mortgage to approximately 25-26 years and saves significant interest — without requiring a large lump sum payment.

Does a lower interest rate always mean I should refinance?

Not always. You need to calculate the break-even point: divide total closing costs by your monthly savings. If closing costs are $6,000 and you save $200/month, break-even is 30 months. If you plan to move or sell before 30 months, refinancing costs you money overall.

How do I get my amortization schedule from my lender?

Federal law (TILA — Truth in Lending Act) requires lenders to provide a full amortization schedule upon request at no charge. You can also generate one with the calculator above — results should match your lender's schedule within rounding differences.

References

→Amortization — Investopedia
→Mortgage Amortization — Consumer Financial Protection Bureau (CFPB)
→Truth in Lending Act (TILA) — Federal Reserve
→Paying Points to Lower Your Mortgage Rate — CFPB
→Understanding Closing Costs — U.S. Department of Housing and Urban Development (HUD)

Sattva

Reviewed by Prana

Updated July 2026

Fintech developer and personal finance writer. All content reviewed for accuracy against established financial standards.