There are many smartphones available under 20000 in the market, but you should look at OnePlus phones under 20000 before buying any other phone.

List of top 5 OnePlus phones under 20000.
ONEPLUS NORD CE4 LITE 5G (SUPER SILVER)

Screen size: 6.67 inches.
Display: AMOLED with 2400 x 1080 pixels.
Camera features: 50MP with optical resolution sensors.
Battery capacity: 5500 mah lithium-ion (Fast charging).
Operating system: OxygenOS.
Snapdragon processor: 2.2 GHz speed.
Storage capacity: 125 GB and 8 GB RAM.
Connector: USB type C, 3.5 mm jack.
Water resistance.
Cellular technology: 5G.
Connectivity: Bluetooth, WIFI and USB connectivity.
ONEPLUS NORD CE4 LITE 5G (MEGABLUE)

Screen size: 6.67 inches.
Display: AMOLED with 2400 x 1080 pixels.
Camera features: 50MP with optical resolution sensors.
Battery capacity: 5500 mah lithium-ion (Fast charging).
Operating system: OxygenOS.
Snapdragon processor: 2.2 GHz speed.
Storage capacity: 125 GB and 8 GB RAM.
Connector: USB type C, 3.5 mm jack.
Water resistance.
Cellular technology: 5G.
Connectivity: Bluetooth, WIFI and USB connectivity.
ONEPLUS NORD CE4 LITE 5G (ULTRA ORANGE)

Screen size: 6.67 inches.
Display: AMOLED with 2400 x 1080 pixels.
Camera features: 50MP with optical resolution sensors.
Battery capacity: 5500 mah lithium-ion (Fast charging).
Operating system: OxygenOS.
Snapdragon processor: 2.2 GHz speed.
Storage capacity: 125 GB and 8 GB RAM.
Connector: USB type C, 3.5 mm jack.
Water resistance.
Cellular technology: 5G.
Connectivity: Bluetooth, WIFI and USB connectivity.
ONEPLUS NORD CE 3 LITE 5G (CHROMIC GRAY)

Screen size: 6.72 INCH (FHD+)
Display: AMOLED with 2400 x 1080 pixels.
Camera features: front camera 16MP, main camera 108MP (2MP depth assist lens and 2MP macro lens).
Video recorded: 1080p/720@30fps, video zoom: 1080p@30fps,720p@30fps, slow motion720p@120fps.
Battery capacity: 5000 mah lithium-ion 30 minutes charge time (67W supervooc).
Operating system: OxygenOS based on Android 13.1.
Processor speed: 2.2GHz
Snapdragon processor: 120Hz refresh rate (Qualcomm 695 5G.)
Storage capacity: 128 GB and 8 GB RAM.
Connector: USB type C.
Water resistance.
Cellular technology: 5G, 4G, LTE.
Connectivity: Bluetooth, WIFI and USB connectivity.
ONEPLUS NORD CE 3 LITE 5G (PASTEL LIME)

Display: AMOLED with 2400 x 1080 pixels.
Camera features: front camera 16MP, main camera 108MP (2MP depth assist lens and 2MP macro lens).
Video recorded: 1080p/720@30fps, video zoom: 1080p@30fps,720p@30fps, slow motion720p@120fps.
Battery capacity: 5000 mah lithium-ion 30 minutes charge time (67W supervooc).
Operating system: OxygenOS based on Android 13.1.
Processor speed: 2.2GHz
Snapdragon processor: 120Hz refresh rate (Qualcomm 695 5G.)
Storage capacity: 128 GB and 8 GB RAM.
Connector: USB type C.
Water resistance.
Cellular technology: 5G, 4G, LTE.
Connectivity: Bluetooth, WIFI and USB connectivity.
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