POPULATION

The population of the province in 2020 was 715,811 person, registering an increase of 26,143 persons over the 2015 population of 689,668.  This figure accounted for 13.87 percent of the region’s total population.  Among the four provinces in the region, Ilocos Sur has the second lowest population, next to Ilocos Norte.Among the municipalities and component cities of the province, Candon City is the most thickly populated with 62,921 persons.  This accounts for 8.79 percent of the total provincial population.  On the other hand, Sigay has the least number of persons with 2,841 or 0.39 percent of the provincial population.  Sugpon follows with 4,759 persons.         

Population Distribution and Percentage of Top Five Municipalities/Cities – Ilocos Sur, 2020

Municipality/City	Total Population	Percent
Ilocos Sur	715,811	100.0
Candon City	62,921	8.79
Vigan City (Capital)	55,921	7.81
Narvacan	45,674	6.38
Santa Cruz	41,379	5.78
Tagudin	40,766	5.70
Other Municipalities	469,150	65.54

Source of Data:  Philippine Statistics Authority

Population Growth

The province of Ilocos Sur posted a total population of 715,811 persons as of August 1, 2020, an increase of 57,224 persons over its population of 658,587 persons in 2010.  The increase in the population count from 2010 to 2020 translated to an average annual Population Growth Rate (PGR) of 0.92 percent, lower than the 1.03 percent average annual PGR of the province for the period 2000 to 2010. Since the first census was taken in 1903, the population of Ilocos Sur increased to more than three times its population size of 189,572 persons in 1903.  In 1990 census, its population surpassed the 500 thousand marks.

Total Population by Census Year

Ilocos Sur, 1903 to 2020

Censal Year		Total Population (in thousands)
1903		189.6
1918		247.5
1939		271.5
1948		276.3
1960		338.1
1970		385.1
1975		419.8
1980		443.6
1990		520.0
1995		545.4
2000		594.2
2007		633.1
2010		658.6
2015		689.7
2020		715.8

Among the two cities and 32 municipalities comprising the province, the City of Candon was the most populous with a population of 62,921, making up 8.79 percent of the total provincial population.  It was followed by the City of Vigan, with 55,921 persons (7.8 percent) and the municipality of Narvacan 45, 674 (6.4 percent).  The rest of the municipalities contributed less than 6.0 percent each. The least populated area was the municipality of Sigay with 0.4 percent share to the total population of the province.  It was also the least populated area in 2010.

Sex ratio rose to 100 males per 98 females

Of the 715.8 total populations in 2020, males accounted to 50.39 percent while females comprised 49.61 percent.  These figures resulted in a sex ratio of 100 males for every 98 females, the same sex ratio was reported in 2010.

Median age increased to 25 years

In 2007, the median age of the population of the province was 25 years, which means that half of the total population was younger than 25 years.  This is higher than the median age of 23 years that was recorded in 2000. Moreover, 31.4 percent of the total populations were under 15 years old.  Children aged 10 to 14 years comprised the largest age group (10.6 percent).  Among the municipalities, San Ildefonso was the fastest growing area in terms of population with an annual growth rate of 2.48 percent from 2000-2007.  This was followed by Galimuyod, Suyo and Candon City.  Over the same period, Candon City and 12 other municipalities registered higher population growth rates than the province.  While the average annual population growth rate at the provincial level (1.0%) was lower than the regional growth rate of 1.10 percent, the City of Vigan and 14 other municipalities registered lower growth rates than the province. This includes the municipalities of Cervantes, Alilem, and Lidlidda that registered negative population growth rates. 

 Population by Municipality/City, Ilocos Sur:   2000, 2007, 2010, 2015, and 2020

MUNICIPALITIES	POPULATION
	2000	2007	2010	2015	2020
1.  ALILEM	6353	6217	6640	6,695	6,949
2.  BANAYOYO	6728	7149	7694	7,748	8,042
3.  BANTAY	30519	33174	34323	35,731	37,085
4.  BURGOS	11175	11459	11679	12,224	12,687
5.  CABUGAO	31459	33847	35706	37,501	38,923
6.  CAOAYAN	17199	18914	18551	19,861	20,614
7.  CERVANTES	14195	14116	16573	17,211	17,863
8.  GALIMUYOD	8879	10310	10011	10,748	11,155
9. G. DEL PILAR	4134	4308	4219	4,875	5,060
10. LIDLIDDA	4022	3798	4398	4,647	4,823
11. MAGSINGAL	25580	27615	28302	30,792	31,959
12. NAGBUKEL	4671	4764	4938	5,259	5,458
13. NARVACAN	38435	41578	42803	44,006	45,674
14. QUIRINO	7130	7866	8535	8,573	8,898
15. SALCEDO	10409	10704	10935	11,288	11,716
16. SAN EMILIO	6717	6920	7427	7,407	7,688
17. SAN ESTEBAN	7174	7779	8072	8,349	8,665
18. SAN ILDEFONSO	5584	6670	7075	7,787	8,082
19. SAN JUAN	23146	23808	25199	26,411	27,412
20. SAN VICENTE	10877	11907	11720	12,758	13,242
21. SANTA	13918	14059	15106	15,340	15,921
22. STA. CATALINA	12537	13284	13597	13,945	14,474
23. STA. CRUZ	34433	35906	37911	39,868	41,379
24. STA. LUCIA	22363	23872	24981	25,402	26,365
25. STA. MARIA	26396	28002	28597	30,321	31,470
26. SANTIAGO	15876	16806	17958	18,759	19,470
27. STO. DOMINGO	24520	25888	27596	27,975	29,035
28. SIGAY	2375	2453	2419	2,737	2,841
29. SINAIT	24070	24896	25427	25,640	26,612
30. SUGPON	3513	3936	3820	4,585	4,759
31. SUYO	9685	10943	10622	11,446	11,880
32. TAGUDIN	34427	35791	38122	39,277	40,766
33. CANDON CITY	50564	56270	57884	60,623	62,921
34. VIGAN CITY	45143	47246	49747	53,879	55,921
ILOCOS SUR	594,206	632,255	658,587	689,668	715,811

Of the total population aged 10 years and over, married persons comprised 46.13 percent, lower than the 1995 figure (47.52 percent).  Single persons constituted 44.33 percent, widowed 5.68 percent, and with other arrangements 2.40 percent.  Separated/divorced persons constituted 0.72 percent, higher than the 0.45 percent recorded in 1995.

More than half of the populations were below 24 years old 

The province had a median age of 24 years, higher than the 1995 median age of 23 years. The province had almost the same number of males and females 348,098, and 342,110 respectively. This figure resulted to a sex ratio of 99.94. There were more males in the age group 0 to 44 years, while more females in the 45 years and above age group. 

Two-thirds belonged to economically active group 

Economically active population aged 15 to 64 years comprised more than 61 percent of the population. Young dependents aged 0 to 14 comprised 32.1 percent while 6.8 percent as old dependents aged 65 years and above. Thus, the overall dependency ratio was 63.76, lower than the 1995 ratio of 70.46. 

Population Density

Population density in the province in 2020 was 277 persons per square kilometer. Based on the latest population count in 2020, Vigan City registered the highest population density with 1,937  persons per square kilometer.  Of the municipalities, Sta. Catalina is the most thickly populated with 1,441 persons per square kilometer, while Sigay had the lowest population density with only 34 persons per square kilometer.

Land Area, Population and Population Density, by City/Municipality,

Ilocos Sur: 1995, 2000, 2007, 2010, 2015, and 2020

	Land Area	Population	Population Density
Municipality
		1995	2000	2007	2010	2015	2020	1995	2000	2007	2010	2015	2020
1. ALILEM	156.2	5,533	6,353	6,217	6,640	6,695	6,949	35	41	40	42	43	44
2. BANAYOYO	31.2	6,140	6,728	7,149	7,694	7,748	8,042	197	216	229	247	248	258
3. BANTAY	76.6	28,128	30,519	33,174	34,323	35,731	37,085	367	398	433	448	466	484
4. BURGOS	44.3	10,101	11,175	11,459	11,679	12,224	12,687	228	252	259	264	276	286
5. CABUGAO	60.1	28,567	31,459	33,847	35,706	37,501	38,923	475	523	563	594	624	648
6. CAOAYAN	26	15,799	17,199	18,914	18,551	19,861	20,614	608	662	727	713	764	793
7. CERVANTES	230.7	13,777	14,195	14,116	16,573	17,211	17,863	60	62	61	72	75	77
8. GALIMUYOD	34.4	8,477	8,879	10,310	10,011	10,748	11,155	246	258	300	291	312	324
9. G. DEL PILAR	104.2	3,940	4,134	4,308	4,219	4,875	5,060	38	40	41	40	47	49
10. LIDLIDDA	29.7	3,700	4,022	3,798	4,398	4,647	4,823	125	135	128	148	156	162
11. MAGSINGAL	85	23,565	25,580	27,615	28,302	30,792	31,959	277	301	325	333	362	376
12. NAGBUKEL	34.9	4,124	4,671	4,764	4,938	5,259	5,458	118	134	137	141	151	156
13. NARVACAN	98.4	35,489	38,435	41,578	42,803	44,006	45,674	361	391	423	435	447	464
14. QUIRINO	240.1	7,295	7,130	7,866	8,535	8,573	8,898	30	30	33	35	36	37
15. SALCEDO	23.1	10,116	10,409	10,704	10,935	11,288	11,716	438	451	463	473	489	507
16. SAN EMILIO	132.8	6,173	6,717	6,920	7,427	7,407	7,688	46	51	52	56	56	58
17. SAN ESTEBAN	23.4	6,508	7,174	7,779	8,072	8,349	8,665	276	307	332	345	357	370
18. SAN ILDEFONSO	17.2	5,232	5,584	6,670	7,075	7,787	8,082	304	325	388	411	453	470
19. SAN JUAN	52.1	21,222	23,146	23,808	25,199	26,411	27,412	407	444	457	484	507	526
20. SAN VICENTE	15.1	9,848	10,877	11,907	11,720	12,758	13,242	652	720	789	776	845	877
21. SANTA	51.6	12,801	13,918	14,059	15,106	15,340	15,921	240	270	272	293	297	309
22. STA. CATALINA	13.5	11,228	12,537	13,284	13,597	13,945	14,474	832	929	984	1,007	1033	1072
23. STA. CRUZ	101.6	30,145	34,433	35,906	37,911	39,868	41,379	297	339	353	373	392	407
24. STA. LUCIA	49.9	20,341	22,363	23,872	24,981	25,402	26,365	408	448	478	500	509	528
25. STA. MARIA	49.6	24,580	26,396	28,002	28,597	30,321	31,470	496	532	565	576	611	634
26. SANTIAGO	74.5	14,843	15,876	16,806	17,958	18,759	19,470	199	213	226	241	252	261
27. STO. DOMINGO	57.8	22,727	24,520	25,888	27,596	27,975	29,035	393	424	448	477	484	502
28. SIGAY	114.6	2,235	2,375	2,453	2,419	2,737	2,841	19	21	21	21	24	25
29. SINAIT	80.7	22,608	24,070	24,896	25,427	25,640	26,612	280	298	309	315	318	330
30. SUGPON	182.8	3,381	3,513	3,936	3,820	4,585	4,759	18	19	22	21	25	26
31. SUYO	124	8,870	9,685	10,943	10,622	11,446	11,880	71	78	88	85	92	96
32. TAGUDIN	58.3	30,697	34427	35,971	38,122	39,277	40,766	526	591	617	654	674	699
33. CANDON CITY	76.9	45,128	50,564	56,270	57,884	60,623	62,921	587	658	732	752	788	818
34. VIGAN CITY	27.4	42,067	45143	47246	49,747	53,879	55,921	1,535	1,535	1,724	1,815	1966	2041
ILOCOS SUR	2579.6	545,385		632,255	658,587	689,668	715,811	211	230	245	255	266	277
594,206

During the year 2010, there are 145,674 households in the province. In 2015, a total of 154,949 households surveyed with an average household size of 5 persons. In 2020, a total of 172,048 households with an average size of 4.1 persons.

Population, No. of Households and Average Household Size By City/Municipality, Ilocos Sur: 2020

Population, Household Population, Number of Households, and Average Household Size
City/Municipality	Total Population	Household Population	Number of Households	Average Household Size
Ilocos Sur	706,009	704,218	172,048	4.1
Alilem	7,361	7,361	1,648	4.5
Banayoyo	7,931	7,928	1,929	4.1
Bantay	37,118	36,949	Total 9,243	4.0
Burgos	12,793	12,787	3,135	4.1
Cabugao	38,884	38,822	9,172	4.2
City of Candon	61,432	61,241	15,125	4.0
Caoayan	19,574	19,567	4,838	4.0
Cervantes	19,449	19,405	4,370	4.4
Galimuyod	10,244	10,244	2,496	4.1
Gregorio del Pilar (Concepcion)	4,472	4,462	956	4.7
Lidlidda	4,705	4,657	1,072	4.3
Magsingal	31,308	31,284	7,840	4.0
Nagbukel	5,465	5,462	1,361	4.0
Narvacan	46,234	46,172	11,269	4.1
Quirino (Angkaki)	9,306	9,242	2,105	4.4
Salcedo (Baugen)	11,110	11,090	2,836	3.9
San Emilio	7,206	7,206	1,672	4.3
San Esteban	8,381	8,369	2,150	3.9
San Ildefonso	8,190	8,173	1,976	4.1
San Juan (Lapog)	26,674	26,660	6,735	4.0
San Vicente	13,118	13,110	3,229	4.1
Santa	14,992	14,946	3,661	4.1
Santa Catalina	14,493	14,493	3,321	4.4
Santa Cruz	41,366	41,297	9,815	4.2
Santa Lucia	25,966	25,923	6,645	3.9
Santa Maria	30,006	29,978	7,453	4.0
Santiago	19,471	19,445	4,821	4.0
Santo Domingo	29,041	29,041	7,346	4.0
Sigay	2,552	2,550	547	4.7
Sinait	25,998	25,998	6,897	3.8
Sugpon	4,930	4,928	949	5.2
Suyo	10,766	10,737	2,742	3.9
Tagudin	41,538	41,373	9,992	4.1
City of Vigan (Capital)	53,935	53,318	12,702	4.2

*Average household size is computed by PPDO

Sex and Age Structure

In 2020, of the total population, 50.52 percent was male while 49.47 percent was female. This resulted in a sex ratio of 100 males for every 98 females. The potential labor force aged 15-64 is 464,335 or 65.94 percent of the total population.  The dependent age group 0-14 years totaled 178,736 or 25.38 percent and the aged (65 years old and over) numbered 61,147 or 8.68 percent of the total population.  Consequently, for every 100 potential earners in the provincial economy, there were about 51 dependents of which 38 were children while the remaining 13 were considered as old age dependents.

Population by Age Groups and by Sex IIocos Sur: 2020

Household Population by Age Group, Sex by City/Municipality: 2020
ILOCOS SUR
Age Group and gender by City/Municipality	Both Sexes	Male	Female
Total	704,218	355,807	348,411
0 – 4	53,016	27,602	25,414
5 – 9	59,988	31,219	28,769
10 – 14	65,732	33,965	31,767
15 – 19	64,483	33,297	31,186
20 – 24	58,781	30,445	28,336
25 – 29	56,268	29,079	27,189
30 – 34	51,235	26,429	24,806
35 – 39	49,720	25,568	24,152
40 – 44	45,825	23,795	22,030
45 – 49	39,850	20,548	19,302
50 – 54	37,299	19,212	18,087
55 – 59	33,199	16,717	16,482
60 – 64	27,675	13,447	14,228
65 – 69	21,470	9,805	11,665
70 – 74	15,166	6,405	8,761
75 – 79	10,630	3,871	6,759
80 years and over	13,881	4,403	9,478

Sex Ratio by Age Group 2020

Sex Ratio by Age Group, Sex by City/Municipality: 2020
ILOCOS SUR
Age Group, Province, and City/Municipality	Both Sexes	Male	Female	Ratio
Total	704,218	355,807	348,411
0 – 4	53,016	27,602	25,414	1:1
5 – 9	59,988	31,219	28,769	1:1
10 – 14	65,732	33,965	31,767	1:1
15 – 19	64,483	33,297	31,186	1:1
20 – 24	58,781	30,445	28,336	1:1
25 – 29	56,268	29,079	27,189	1:1
30 – 34	51,235	26,429	24,806	1:1
35 – 39	49,720	25,568	24,152	1:1
40 – 44	45,825	23,795	22,030	1:1
45 – 49	39,850	20,548	19,302	1:1
50 – 54	37,299	19,212	18,087	1:1
55 – 59	33,199	16,717	16,482	1:1
60 – 64	27,675	13,447	14,228	1:1
65 – 69	21,470	9,805	11,665	1:1
70 – 74	15,166	6,405	8,761	1:1
75 – 79	10,630	3,871	6,759	1:1
80 years and over	13,881	4,403	9,478	0

Source: Philippine Statistics Authority 2020 Census of Population

Household Population 5 Years Old and Over by Highest Grade/Year Completed, Age/Age Group, and Sex, Ilocos Sur: 2020

Highest Grade/Year Completed, and Sex	Household Population 5 Years Old & Over	Male	Female
Ilocos Sur
Both Sexes	626,322	314,757	311,565
No Grade Completed	12,797	6,518	6,279
Pre-School	15,588	8,102	7,486
Elementary	246	155	91
1st – 4th grade	190,542	99,505	91,037
5th – 6th grade	84,426	44,822	39,604
Graduate	25,759	13,630	12,129
High School	80,357	41,053	39,304
Undergraduate	233,026	122,965	110,061
Graduate	75,059	40,496	34,563
Post Secondary	157,967	82,469	75,498
Undergraduate	23,293	9,649	13,644
Graduate	870	421	449
College Undergraduate	22,423	9,228	13,195
Academic Degree Holder	68,183	32,981	35,202
Post Baccalaureate	81,188	34,293	46,895
Not Stated	1,252	491	761

Total Population 10 Years Old and Over by Age Group and Marital Status Ilocos Sur: 2020

Age Group	Total Population 10 Yrs Old & Over	Single	Married	Widowed	Divorced/ Separated	Common-Law/ Live-in	Unknown
Ilocos Sur
Both Sexes	560,822	227,787	257,286	34,157	6,924	34,609	59
Below 20	126,060	122,760	807	4	24	2,463	2
20 – 24	59,716	40,695	11,127	56	236	7,599	3
25 – 29	54,089	21,903	24,420	164	573	7,018	11
30 – 34	52,219	12,550	33,192	343	833	5,295	6
35 – 39	47,762	7,332	34,876	578	1,042	3,928	6
40 – 44	41,072	4,985	31,514	916	962	2,692	3
45 – 49	39,350	4,522	30,324	1,474	947	2,076	7
50 –  54	34,810	3,449	26,704	2,396	798	1,458	5
55 –  59	29,324	2,581	21,988	3,167	625	957	6
60 –  64	23,517	2,013	16,313	4,221	410	557	3
65 –  69	17,429	1,545	10,884	4,488	221	289	2
70 –  74	12,873	1,180	7,004	4,425	126	135	3
75 –  79	10,438	947	4,759	4,582	70	80	–
80 &     Over	12,163	1,325	3,374	7,343	57	62	2

  Source of Data: 2020 Census of Population

POPULATION AND SETTLEMENTS

POPULATION SIZE

The population of the province in 2020 was 704,218 person, registering an increase of 14,550 person over the 2015 population of 689,668.  This figure accounted for 13.64 percent of the region’s total population.  Among the four provinces in the region, Ilocos Sur has the second lowest population, next to Ilocos Norte which only has 609.558 person (11.73%). Pangasinan is the most populated province with 3,163,193

.

(59.07%) followed by La Union with 822,352 (15.56%)

Among the municipalities and component cities of the province, Candon City is the most thickly populated with 61,432 person.  This accounts for 8.79% of the total provincial population.  On the other hand, Sigay has the least number of persons with 2,737 or 0.4 percent of the provincial population.  Sugpon follows with 4,585 person. 

POPULATION GROWTH

The Average Population Growth Rate (APGR) of the province for the period 2015 to 2020 is 0.88 percent, lower than the Regional APGR of 1.09 percent and much lower than the national growth rate of 1.72 percent during the same period. Ilocos Norte registered the lowest population growth rate (0.83%) as compared to Pangasinan (1.18%) and La Union (1.12%). 

Between 2010 and 2020, its population grew at an average 

Population, Annual Population Growth Rate, Density

Annual Population Growth Rate by Municipality2010– 2015

Map 5. Annual Population Growth Rate by Municipality2015 – 2020

growth rate of 1.03%, lower than the 1.34 percent average annual PGR of the province for the period 1990 to 2000. 

Source:  National Economic Development Authority

Candon City being the largest urban center in the province, is the most thickly populated with 60,623 persons accounting to 8.79% of the total provincial population.  It has an annual APGR of 0.88% for the period of 2010-2015, the same with the province’s APGR.  Vigan City, the provincial capital, with a population of 53,879 person, is the core of Metro Vigan which is composed of the municipalities of Caoayan, Sta. Catalina, San Vicente and Bantay. It is the center of education, trade and commerce and is expected to continue to expand its direct area of influence over the surrounding municipalities. Vigan City is also a heritage site as declared by the UNESCO and included in the Seven Wonder Cities of the World. Being such, it is one of the tourist destinations in the north. Although Candon City is the most thickly populated among the cities/municipalities comprising the province, yet it is the third least populated city in the Region, next to the cities of Batac and Vigan being the least.

As compared to Regional Density of 390 persons/ sq. km, and the Philippines with 337, the Province‘s population density is lower with 266 and second lowest within the region.

Population Share by Province, Region 1

Province	Population	Pop. % Share	APGR	Pop. Density
2010	2015	2010	2015	2010	2015	2010	2015
Ilocos Norte	568017	593081	11.96	11.73	1.00	0.83	167	171
Ilocos Sur	658587	689668	13.87	13.64	1.03	0.88	255	266
La Union	741906	786653	15.63	15.56	1.21	1.12	496	525
Pangasinan	2779862	2986726	58.54	59.07	1.34	1.18	517.84	542
TOTAL / R1	4748372	5056110	100	100	1.23	1.09	354	390